The Case Theme User plugin for WordPress is vulnerable to Authentication Bypass in all versions up to, and including, 1.0.3. This is due to the plugin not properly logging in a user with the data that was previously verified through the facebook_ajax_login_callback() function. This makes it possible for unauthenticated attackers to log in as administrative users, as long as they have an existing account on the site which can easily be created by default through the temp user functionality, and access to the administrative user's email.