Apereo CAS 2FA login improper authentication

A vulnerability was found in Apereo CAS 6.6. It has been classified as critical. This affects an unknown part of the file /login?service of the component 2FA. The manipulation leads to improper authentication. It is possible to initiate the attack remotely. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.