A vulnerability was detected in MaxSite CMS up to 109.3. This affects an unknown part of the component Redirect Plugin. The manipulation of the argument f_all/f_all404 results in cross site scripting. The attack can be launched remotely. The exploit is now public and may be used. Upgrading to version 109.4 is able to mitigate this issue. The patch is identified as 8a3946bd0a54bfb72a4d57179fcd253f2c550cd7. You should upgrade the affected component. The vendor was informed early about this issue. They classify it as a "Self-XSS". They deployed a countermeasure: "Nevertheless, we consider this a violation of secure coding standards. The lack of filtering via htmlspecialchars() has already been fixed in the latest patch to prevent incorrect data display."