Kyverno is a policy engine designed for cloud native platform engineering teams. Prior to versions 1.17.2 and 1.16.4, an unchecked type assertion in the `forEach` mutation handler allows any user with permission to create a `Policy` or `ClusterPolicy` to crash the cluster-wide background controller into a persistent CrashLoopBackOff. The same bug also causes the admission controller to drop connections and block all matching resource operations. The crash loop persists until the policy is deleted. The vulnerability is confined to the legacy engine, and CEL-based policies are unaffected. Versions 1.17.2 and 1.16.4 fix the issue.
https://github.com/kyverno/kyverno/security/advisories/GHSA-fpjq-c37h-cqcv
https://github.com/kyverno/kyverno/commit/80e728c2283a0c65e5adb02d8a907106e6ebe7e3
https://github.com/kyverno/kyverno/commit/76c8fdbe87328722e099e1fd44c3f21c9f7809cb