Claroline 13.5.7 and prior allows an authenticated attacker to elevate privileges via the arbitrary creation of a privileged user. By combining the XSS vulnerability present in several upload forms and a javascript request to the present API, it is possible to trigger the creation of a user with administrative rights by opening an SVG file as an administrator user.
Claroline 13.5.7 and prior is vulnerable to Cross Site Scripting (XSS). An attacker can obtain javascript code execution by adding arbitrary javascript code in the 'Location' field of a calendar event.