Description
A flaw was found in the Application Subscription controller (multicluster-operators-subscription) of Red Hat Advanced Cluster Management for Kubernetes (ACM). A user with namespace-scoped "edit" privileges in an ACM hub namespace can create a Channel resource pointing to a Helm repository they control and a Subscription resource referencing it. The app-subscription controller fetches and applies the Helm chart contents with its own elevated authority, without verifying whether the subscription creator holds the "open-cluster-management:subscription-admin" role and without restricting applied resources to the subscription namespace. This allows the attacker to include cluster-scoped resources in the Helm chart, such as a ClusterRoleBinding granting the attacker's ServiceAccount the "cluster-admin" ClusterRole. Successful exploitation results in full cluster-admin privilege escalation. This contradicts the ACM documentation which states that non-subscription-admin users should have resources deployed into the subscription namespace only.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.11
Default version status: affected
1787263584 to < *unaffected
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.13
Default version status: affected
1787263693 to < *unaffected
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.14
Default version status: affected
1787170830 to < *unaffected
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.15
Default version status: affected
1787240030 to < *unaffected
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.16
Default version status: affected
1787242321 to < *unaffected
Red Hat Red Hat Advanced Cluster Management for Kubernetes 2.17
Default version status: affected
1787242108 to < *unaffected
References
- https://access.redhat.com/errata/RHSA-2026:60386 ↗
- https://access.redhat.com/errata/RHSA-2026:60387 ↗
- https://access.redhat.com/errata/RHSA-2026:60388 ↗
- https://access.redhat.com/errata/RHSA-2026:60389 ↗
- https://access.redhat.com/errata/RHSA-2026:60390 ↗
- https://access.redhat.com/errata/RHSA-2026:60391 ↗
- https://access.redhat.com/security/cve/CVE-2026-10090 ↗
- https://bugzilla.redhat.com/show_bug.cgi?id=2483292 ↗