Vulnerability · Published Aug 26, 2026 · Assigned by GitHub_M

CVE-2026-54523Kyverno: NamespacedGeneratingPolicy generator.apply() namespace argument unvalidated -- background controller creates RoleBindings in any namespace including kube-system

Critical 9.6

In plain English

A critical-severity missing authorization in kyverno from kyverno. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 41% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)9.6Critical

Exploit odds (30 days)0.5%top 59.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack tooling1Public PoC

Official 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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Go	github.com/kyverno/kyverno	1.18.2	GHSA-79gf-7frw-68m9
Go	github.com/kyverno/kyverno	1.18.2	GO-2026-6296

Affected products (as reported)

Vendor	Product	Versions
kyverno	kyverno	>= 1.18.0, < 1.18.2

Weakness: CWE-862 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N

References

https://github.com/kyverno/kyverno/security/advisories/GHSA-79gf-7frw-68m9 x_refsource_CONFIRM
https://github.com/kyverno/kyverno/pull/16238 x_refsource_MISC
https://github.com/kyverno/kyverno/commit/0919553c0ea1904f8d891280c92018da97946a06 x_refsource_MISC
https://github.com/kyverno/kyverno/commit/5164bcdeda5b57678bc2d7a03ecc2cbb02982dae x_refsource_MISC
https://github.com/kyverno/sdk/commit/6573937441443e1ba5af9fbb28d5c0f20297f9df x_refsource_MISC
https://github.com/kyverno/kyverno/releases/tag/v1.18.2 x_refsource_MISC