A flaw was found in the governance-policy-addon-controller component of Red Hat Advanced Cluster Management for Kubernetes. A user with permissions to annotate the namespaced ManagedClusterAddOn resource can override the governance-policy container image. This allows an attacker to run a controlled image with cluster-admin privileges on the managed cluster, leading to arbitrary code execution and privilege escalation.
To mitigate this issue, restrict users' ability to annotate ManagedClusterAddOn resources within the hub cluster. Ensure that only trusted administrators have namespace-level annotate permissions on these resources. Regularly review and audit permissions related to ManagedClusterAddOn resources to prevent unauthorized modifications. If a service is restarted or reloaded, these permission changes will persist.