Stored Cross-Site Scripting Vulnerability in Custom Field Suite for WordPress

Summary

The Custom Field Suite plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the the 'cfs[post_title]' parameter versions up to, and including, 2.6.7 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.