Multiple cross-site scripting (XSS) vulnerabilities in WWWthreads 5.4.2 and earlier allow remote attackers to inject arbitrary web script or HTML via the Cat parameter to (1) dosearch.php, (2) postlist.php, (3) showmembers.php, (4) faq_english.php, (5) online.php, (6) login.php, (7) newuser.php, (8) wwwthreads.php, (9) search.php, or (10) postlist.php.