EFAK through 5.1.0 Privilege Escalation via /api/users REST API

EFAK through 5.1.0 contains a missing authorization vulnerability that allows authenticated low-privilege users to manage accounts because the /api/users endpoints lack administrator role checks. Attackers can send POST, PUT, or DELETE requests to UserController to grant themselves ROLE_ADMIN, create administrators, or delete users, gaining control of managed Kafka clusters.