GHSA-f9g8-6ppc-pqq4: Kyverno: ServiceAccount token leaked to external servers via apiCall service URL

Kyverno’s apiCall feature in ClusterPolicy automatically attaches the admission controller’s ServiceAccount token to outgoing HTTP requests. The service URL has no validation — it can point anywhere, including attacker-controlled servers. Since the admission controller SA has permissions to patch webhook configurations, a stolen token leads to full cluster compromise.