Kyverno: Cross-Namespace Read Bypasses RBAC Isolation (CVE-2026-22039 Incomplete Fix)

Kyverno is a policy engine designed for cloud native platform engineering teams. The patch for CVE-2026-22039 fixed cross-namespace privilege escalation in Kyverno's `apiCall` context by validating the `URLPath` field. However, the ConfigMap context loader has the identical vulnerability — the `configMap.namespace` field accepts any namespace with zero validation, allowing a namespace admin to read ConfigMaps from any namespace using Kyverno's privileged service account. This is a complete RBAC bypass in multi-tenant Kubernetes clusters. An updated fix is available in version 1.17.2.