CIS warns of authentication bypass in pac4j-jwt JWT library

Editorial brief

CIS published an advisory about a vulnerability in pac4j-jwt (JwtAuthenticator) that could allow an unauthenticated remote attacker to bypass authentication and impersonate any user, including an administrator. The flaw affects Java applications using the pac4j security framework for JSON Web Token validation. Organizations using pac4j-jwt should review the CIS advisory and assess impact on their systems, particularly where JWT-based authentication supports compliance with NIST SP 800-171 access control and authentication requirements.