The RSS Aggregator by Feedzy – Feed to Post, Autoblogging, News & YouTube Video Feeds Aggregator plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's shortcode(s) in all versions up to, and including, 4.3.3 due to insufficient input sanitization and output escaping on the Content-Type field of error messages when retrieving an invalid RSS feed. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
https://blog.sucuri.net/2024/04/wordpress-vulnerability-patch-roundup-april-2024.html
https://plugins.trac.wordpress.org/changeset/3012849/feedzy-rss-feeds