CVE-2026-122306 Kyverno before 1.19.2 Denial of Service via Exponential-Time Wildcard Matching

What is CVE-2026-122306?

CVE-2026-122306 is a high-severity vulnerability in kyverno, published on 5 Nov 2026.

Official description

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.

Weakness: CWE-407

Which versions are affected by CVE-2026-122306?

It affects 1 product.

Products include Kyverno.

How do I fix CVE-2026-122306?

No fix has been published for CVE-2026-122306 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-122306 being exploited?

There is no known exploitation of CVE-2026-122306 in the wild and no public exploit code.

Other vulnerabilities in kyverno

• CVE-2026-22039 Kyverno Cross-Namespace Privilege Escalation via Policy apiCall Critical 10.0
• CVE-2026-4789 CVE-2026-4789 Critical 9.8
• CVE-2026-122303 Kyverno 1.17.0 before 1.19.2 Cross-Namespace Resource Overwrite via NamespacedMutatingPolicy Critical 9.4
• CVE-2026-122304 Kyverno 1.17.0 before 1.19.2 Privilege Escalation via CleanupPolicy Context Loader Critical 9.4
• CVE-2026-122310 Kyverno 1.19.1 before 1.19.2 Privilege Escalation via Policy apiCall urlPath Critical 9.4

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• GitHub advisory
• How this page is made

Also known as GHSA-867m-46wg-c2rf, GHSA-8mrj-27wr-599g.