CVE-2026-75528: Broken Link Checker <= 2.4.13 - Unauthenticated Stored Cross-Site Scripting via Comment Author URL / Link Log
The Broken Link Checker plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Comment Author URL / Link Log in all versions up to, and including, 2.4.13 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.
Affected Software
Event History
Frequently Asked Questions
Who is exposed to this issue?
WordPress sites running Broken Link Checker version 2.4.13 or earlier are affected. An attacker can initiate the attack without authentication by submitting a comment whose author URL points to an attacker-controlled server.
What must happen for exploitation to succeed?
The attacker-controlled server must redirect the submitted comment-author URL to a URL containing an HTML or JavaScript payload. An administrator must then use the plugin's standard dismiss-and-recheck workflow for that link, causing the redirected payload URL to be stored verbatim in the link log.
When does the injected script execute?
The stored script executes when a user accesses the injected page. The available data specifically identifies the plugin's link log as the location where the payload is stored.