multicluster engine for Kubernetes 2.1 vulnerability

A flaw was found in the cluster-curator-controller component of multicluster engine (MCE). A tenant with create or update permissions on ClusterCurator resources can inject an arbitrary Job specification. This is possible because the CreateJob() function does not validate user-controlled input when unmarshaling the spec.install.overrideJob raw extension. Successful exploitation allows the injected Job to run with the controller's elevated privileges, leading to arbitrary code execution and privilege escalation, potentially accessing cluster-wide secrets.

Published 12 Aug 2026Updated 5 Sep 20268 sources
CVSS 9.9

What happened

A flaw was found in the cluster-curator-controller component of multicluster engine (MCE). A tenant with create or update permissions on ClusterCurator resources can inject an arbitrary Job specification. This is possible because the CreateJob() function does not validate user-controlled input when unmarshaling the spec.install.overrideJob raw extension. Successful exploitation allows the injected Job to run with the controller's elevated privileges, leading to arbitrary code execution and privilege escalation, potentially accessing cluster-wide secrets.

Affected versions

multicluster engine for Kubernetes 2.1: See vendor advisory Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

  • Apply vendor-provided updates or mitigations.
  • Review affected product exposure and access logs.

Public PoC references

No public PoC reference has passed the current publication threshold.