Just Custom Fields <= 3.3.2 - Cross-Site Request Forgery via AJAX actions

The Just Custom Fields plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 3.3.2. This is due to missing or incorrect nonce validation on several AJAX function. This makes it possible for unauthenticated attackers to invoke this functionality intended for admin users via a forged request granted they can trick a site administrator into performing an action such as clicking on a link. This enables subscribers to manage field groups, change visibility of items among other things.