WP RSS Aggregator < 4.19.3 - Subscriber+ Stored Cross-Site Scripting

The WP RSS Aggregator WordPress plugin before 4.19.3 does not sanitise and escape data before outputting it in the System Info admin dashboard, which could lead to a Stored XSS issue due to the wprss_dismiss_addon_notice AJAX action missing authorisation and CSRF checks, allowing any authenticated users, such as subscriber to call it and set a malicious payload in the addon parameter.