Classic Editor Addon < 2.6.4 - Cross-Site Request Forgery

The Classic Editor Addon plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to, and including, 2.6.3. This is due to inclusion of a vulnerable version of the wp-dependency-installer library. This makes it possible for unauthenticated attackers to install and activate arbitrary plugins via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.