Frontend File Manager <= 21.3 - Cross-Site Request Forgery to Plugin Settings Update

The Frontend File Manager plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to, and including, 21.3. This is due to missing or incorrect nonce validation on the wpfm_save_settings function. This makes it possible for unauthenticated attackers to modify the plugin's settings, via forged request granted they can trick a site administrator into performing an action such as clicking on a link.