Cross-site scripting in Forma LMS version

Forma LMS version 3.1.0 and earlier are affected by an Cross-Site scripting vulnerability, that could allow a remote attacker to inject javascript code on the “back_url” parameter in appLms/index.php?modname=faq&op=play function. The exploitation of this vulnerability could allow an attacker to steal the user´s cookies in order to log in to the application.