Hi,The MFA features of the Apereo CAS server have a critical security vulnerability that allows one to bypass follow-up authentication factors.If your CAS deployment uses an MFA integration other than one with Duo Security, you MUST upgrade the version of your CAS server to the latest appropriate release:- using the 5.3.x stream, upgrade to the version 5.3.3- using the 5.2.x stream, upgrade to the version 5.2.7- using older versions, upgrade to the version 5.2.7.We will provide more details after a grace period of two weeks. For more information on the security policy, please see: https://apereo.github.io/cas/development/planning/Security-Guide.htmlThanks.Best regards,Jérôme