Vulnerable Systems:
* Related Posts Wordress Plugin
This advisory describes multiple Stored Cross Site Scripting (XSS) vulnerabilities and one Cross Site Request Forgery (CSRF) vulnerability on the plugin. As a result, an attacker can gain elevated access privileges to sensitive page content, session cookies, and a variety of other information maintained by the browser on behalf of the WordPress administrator user. Furthermore, the attacker can perform actions with administrative powers.
This problem was confirmed in the latest version of the plugin, other versions maybe also affected.
The plugin's configuration page is vulnerable to Stored Cross Site Scripting. The three fields wp_relatedposts_ title, wp_relatedposts_num and wp_relatedposts_type are received through POST or GET and included on the response page with little sanitization.
Another vulnerable piece of code is the one which prints the related posts list. The title (received through the parameter wp_relatedposts_title is included with little sanitization into suchs lists. The vulnerable code is shown next:
These vulnerabilities allow an attacker to insert HTML/JavaScript commands to be interpreted in the session of an authenticated administrator user.
Since the plugin's configuration page is not protected against Cross Site Request Forgery, the exploitation permits the attacker to inject configuration values.
Proof of concept exploitation code is available to interested parties.
