High [CVE-2026-66793] arbitrary container image override via ManagedClusterAddOn annotation enables RCE on spoke
This high-severity Red Hat Linux advisory covers CVE-2026-66793 affecting Red Hat Advanced Cluster Management for Kubernetes 2.
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Summary
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. This Critical vulnerability in Red Hat Advanced Cluster Management for Kubernetes enables remote code execution on managed clusters.
Red Hat severity: Important — CVSS 8.8 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H). Weakness: CWE-20.
Red Hat does not currently list a fixing RHSA for this CVE.
Affected product named by the advisory: Red Hat Advanced Cluster Management for Kubernetes 2.
Affected versions
No affected-version range was extracted from the source record. The vendor advisory is authoritative — check it before change work.
Official advisory · high-confidence parse· fetched 1 hour ago·verify at source
Fixed versions
No fixed release is recorded yet. That does not prove no patch exists — confirm against the vendor advisory.
Official advisory · high-confidence parse· fetched 1 hour ago·verify at source
Mitigation checklist
- 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.
Official advisory · high-confidence parse· fetched 1 hour ago·verify at source
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