Improper Access Control vulnerability in the Account REST API of Keycloak. The flaw is caused by insufficient validation of the authentication Level of Assurance (LoA) before allowing credential management actions. An attacker who has obtained a victim’s primary credentials (username and password) can authenticate at a lower LoA and delete the victim’s registered OTP/MFA credential without completing step-up authentication. The attacker can then register their own MFA device, effectively achieving full account takeover. Exploitation requires network access and valid credentials but no user interaction, resulting in compromise of account integrity and partial confidentiality impact.