Broken Link Checker < 2.4.13.1 - Unauthenticated Stored XSS via Comment Author URL / Link Log

Description

The plugin is vulnerable to Stored Cross-Site Scripting via Comment Author URL / Link Log due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. Exploitation requires an administrator to perform the plugin's standard dismiss-and-recheck workflow on a link submitted by the attacker via the WordPress comment author URL field, after which the attacker's HTTP server issues a redirect to a URL containing an HTML/JavaScript payload that is stored verbatim in the link log.