Cross-site scripting (XSS) vulnerability in register.php in Phorum 5.1.18 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors. NOTE: the vendor disputes this vulnerability, stating that "The characters are escaped properly.
http://www.vupen.com/english/advisories/2007/0410
http://www.securityfocus.com/bid/22297
http://www.securityfocus.com/archive/1/458467/100/0/threaded
http://www.securityfocus.com/archive/1/458461/100/0/threaded