A security flaw has been discovered in Rebuild up to 4.1.3. Affected by this issue is some unknown functionality of the component Comment/Guestbook. Performing manipulation results in cross site scripting. It is possible to initiate the attack remotely. Upgrading to version 4.1.4 can resolve this issue. It is suggested to upgrade the affected component. According to the researcher the vendor has confirmed the flaw and fix in a private issue response.