Input validation vulnerability in Popup by Supsystic 1.10.19

The Popup by Supsystic plugin for WordPress is vulnerable to a type of cyber attack known as Cross-Site Request Forgery. Up to version 1.10.19 of the plugin, it does not have the correct security measures in place to protect against this type of attack. This means that an attacker, without having to authenticate or log in, can trick an authorized user into clicking on a malicious link and unknowingly perform certain actions, such as sending a test email or saving plugin options.