SECURITYCRITICALCVE-2026-122304

CVE-2026-122304: Kyverno CleanupPolicy Context Loader Lets Namespace Admins Escape Confinement

Kyverno 1.17.0 to before 1.19.2 builds the cleanup controller's context loader with a nil policy, so namespaced CleanupPolicies escape confinement (CVSS 9.9).

Dylan H.

Security Team

November 5, 2026
2 min read
CVE-2026-122304: Kyverno CleanupPolicy Context Loader Lets Namespace Admins Escape Confinement

Critical severity

Rated critical. Prioritise patching — see the remediation guidance below.

Affected Products

  • Kyverno 1.17.0 up to, but not including, 1.19.2

CVE-2026-122304: Kyverno Cleanup Controller Authorization Bypass

CVE-2026-122304 is an authorization bypass in Kyverno from 1.17.0 up to (not including) 1.19.2, scored CVSS 9.9 (Critical).

The cleanup controller builds its context loader with a nil policy, so the checks that normally confine a namespaced policy to its own namespace are skipped. A namespace admin can create a namespaced CleanupPolicy that uses apiCall or globalReference context entries and thereby escape namespace confinement.

Key Facts

FieldDetail
CVECVE-2026-122304
SeverityCritical (CVSS 9.9)
ProductKyverno cleanup controller
Affected1.17.0 up to, but not including, 1.19.2
Fixed in1.19.2
PrerequisiteAbility to create a namespaced CleanupPolicy
Published2026-11-05

Remediation

  1. Upgrade Kyverno to 1.19.2 or later.
  2. Restrict creation of namespaced CleanupPolicy objects to trusted administrators until patched.
  3. Audit existing CleanupPolicies that use apiCall or globalReference context entries.
  4. Review cleanup controller activity for deletions or reads outside the policy's own namespace.

This is one of several Kyverno multi-tenancy flaws fixed in 1.19.2, alongside CVE-2026-122302, CVE-2026-122303, CVE-2026-122310 and CVE-2026-122311. Treat the upgrade as a single remediation.

References