CVE-2021-4396

The Rucy plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to, and including, 0.4.4. This is due to missing or incorrect nonce validation on the save_rc_post_meta() function. This makes it possible for unauthenticated attackers to save post meta via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.

Source: CVE-2021-4396