This vulnerability arises from the Application propagation controller in Red Hat Advanced Cluster Management for Kubernetes 2 failing to validate the ocm-managed-cluster annotation from Application Custom Resources. A tenant with Application creation permissions on the hub cluster can exploit this to redirect ManifestWorks to arbitrary managed clusters, bypassing authorization controls. This leads to forced synchronization of attacker-controlled manifests by ArgoCD on spoke clusters, enabling arbitrary code execution or privilege escalation. The flaw is classified as an unintended proxy or 'Confused Deputy' (CWE-441) and has a CVSS 3.1 base score of 9.9, indicating critical severity. Red Hat has not yet provided an official fix or mitigation that meets their standards for ease of use, applicability, and stability.

An attacker with low privileges (Application creation permissions) on the hub cluster can escalate privileges to cluster-admin on any connected spoke cluster. This allows execution of arbitrary code or commands on those clusters, compromising confidentiality, integrity, and availability. The vulnerability affects the security boundary between the hub and managed clusters, enabling significant privilege escalation and potential full cluster compromise.

Currently, Red Hat states that no mitigation or fix is available that meets their criteria for ease of use, applicability, and stability. Users should monitor the Red Hat advisory for updates. Until an official fix or mitigation is released, restricting Application creation permissions to trusted users and minimizing the attack surface are recommended as interim risk reduction measures.