The Login/Signup Popup plugin for WordPress is vulnerable to authorization bypass due to missing capability checks on several functions in versions up to, and including, 1.4. This makes it possible for authenticated attackers to inject arbitrary web scripts into the plugin settings that execute if they can successfully trick a user into performing an action such as clicking on a link.

The Login/Signup Popup plugin for WordPress is vulnerable to authorization bypass due to missing capability checks on several functions in versions up to, and including, 1.4. This makes it possible for authenticated attackers to inject arbitrary web scripts into the plugin settings that execute if they can successfully trick a user into performing an action such as clicking on a link.