Multiple cross-site scripting (XSS) vulnerabilities in Claroline 1.8.3 allow remote attackers to inject arbitrary web script or HTML via the PATH_INFO (PHP_SELF) to (1) index.php, (2) demo/claroline170/index.php, and possibly other scripts.
http://www.vupen.com/english/advisories/2007/2402
http://www.securityfocus.com/bid/24742
http://www.claroline.net/forum/viewtopic.php?t=11920