A flaw was found in the OIDC implementation of Keycloak, specifically within the Device Authorization Grant flow. This component allows devices with limited input capabilities to obtain security tokens. The issue occurs because the flow fails to check the minimum authentication level required by a client configuration. This allows an attacker who has stolen a user's password to bypass mandatory multi-factor authentication and gain unauthorized access to the Keycloak Admin REST API.
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.