High · published September 24, 2026
phpMyFAQ is an open source FAQ web application. A stored cross-site scripting (XSS) vulnerability in versions prior to 4.2.0-alpha allows any unauthenticated user (or low-privileged registered user) to inject arbitrary JavaScript that executes in an administrator's browser when they review or edit a user-submitted FAQ entry. This leads to admin account takeover via session theft. The vulnerability exists because `html_entity_decode()` converts HTML entities into executable HTML after `strip_tags()` has already passed them through, and the admin template renders the content with Twig's `|raw` filter without any output sanitization. Version 4.2.0-alpha fixes the issue.