Custom Field Suite <= 2.6.7 - Authenticated (Contributor+) PHP Code Injection via Loop Custom Field

The Custom Field Suite plugin for WordPress is vulnerable to PHP Code Injection in all versions up to, and including, 2.6.7 via the Loop custom field. This is due to insufficient sanitization of input prior to being used in a call to the eval() function. This makes it possible for authenticated attackers, with contributor-level access and above, to execute arbitrary PHP code on the server.