The Youtube Feeder WordPress plugin is vulnerable to Cross-Site Request Forgery via the printAdminPage function found in the ~/youtube-feeder.php file which allows attackers to inject arbitrary web scripts, in versions up to and including 2.0.1.
https://www.wordfence.com/vulnerability-advisories/#CVE-2021-34633
https://plugins.trac.wordpress.org/browser/youtube-feeder/trunk/youtube-feeder.php#L669