CVE-2026-54523
From 1.18.0 until 1.18.2, the NamespacedMutatingPolicy CEL compiler exposes the generator library to matchConditions, allowing a namespace-scoped policy to invoke generator.apply(namespace, resources) with an arbitrary target namespace.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.40%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Kyverno is a policy engine designed for cloud native platform engineering teams. From 1.18.0 until 1.18.2, the NamespacedMutatingPolicy CEL compiler exposes the generator library to matchConditions, allowing a namespace-scoped policy to invoke generator.apply(namespace, resources) with an arbitrary target namespace. The validation in pkg/cel/policies/mpol/validate.go checks that the policy compiles but does not enforce namespace scope, and GenerateResources in pkg/cel/libs/context.go does not reject the cross-namespace target. A user who can create NamespacedMutatingPolicy objects in one namespace can cause the admission controller, operating with cluster-wide privileges, to create ConfigMaps, NetworkPolicies, Secrets, RoleBindings, and other resources in another namespace, enabling unauthorized modification and potential privilege escalation. This issue is fixed in version 1.18.2.
- CVSS 3.1
- 9.6 CRITICALCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
- EPSS
- 0.40% probability · 34th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-862
- Source
- security-advisories@github.com
References
- https://github.com/kyverno/kyverno/commit/0919553c0ea1904f8d891280c92018da97946a06
- https://github.com/kyverno/kyverno/commit/5164bcdeda5b57678bc2d7a03ecc2cbb02982dae
- https://github.com/kyverno/kyverno/pull/16238
- https://github.com/kyverno/kyverno/releases/tag/v1.18.2
- https://github.com/kyverno/kyverno/security/advisories/GHSA-79gf-7frw-68m9
- https://github.com/kyverno/sdk/commit/6573937441443e1ba5af9fbb28d5c0f20297f9df
- https://github.com/kyverno/kyverno/security/advisories/GHSA-79gf-7frw-68m9
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.