Kyverno from 1.17.0 before 1.19.2 contains a privilege escalation vulnerability that allows namespace-scoped tenants to modify resources in other namespaces through NamespacedMutatingPolicy targetMatchConstraints.expression CEL output lacking namespace checks. Attackers can emit a literal target such as another tenant's RoleBinding, which the cluster-wide background controller then mutates to add attacker subjects or alter Roles, NetworkPolicies, and ConfigMaps.
Kyverno before 1.19.2 contains a privilege escalation vulnerability that allows namespace admins to create resources beyond their RBAC because generate-rule admission checks verify the controller's permissions, not the author's. Attackers can create a namespaced Policy with generate rules targeting other namespaces or cluster-scoped kinds, making the background controller create or clone resources cluster-wide.
Kyverno before 1.19.2 contains a denial of service vulnerability that allows namespaced policy authors to exhaust admission controller CPU by submitting pathological wildcard patterns. Attackers can create a Policy with crafted match and exclude names evaluated by ValidateMatchExcludeConflict, pinning cores and causing cluster-wide webhook timeouts that block resource operations.
Kyverno before 1.19.2 contains a policy bypass vulnerability in the admissionpolicygenerator controller, which folds PolicyExceptions into generated ValidatingAdmissionPolicies while ignoring the --enablePolicyException, --exceptionNamespace, and policy kind gates. Users with namespaced create rights on PolicyExceptions can inject negated matchConditions into the generated policies to admit violating resources, bypassing cluster-wide enforcement.
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.