The WP RSS Aggregator plugin for WordPress is vulnerable to Server-Side Request Forgery in all versions up to, and including, 4.23.5 via the RSS feed source in admin settings. This makes it possible for authenticated attackers, with administrator-level access and above, to make web requests to arbitrary locations originating from the web application and can be used to query and modify information from internal services.
https://plugins.trac.wordpress.org/changeset/3029525/wp-rss-aggregator