CVE-2026-122303

CRITICAL 9.9

Kyverno 1.17.0 before 1.19.2 Cross-Namespace Resource Overwrite via NamespacedMutatingPolicy

CVSS Score

9.9

EPSS Score

0.0%

EPSS Percentile

0th

Kyverno from 1.17.0 before 1.19.2 contains an authorization bypass vulnerability that allows namespace tenants to overwrite resources in other namespaces via NamespacedMutatingPolicy mutate-existing targetMatchConstraints.expression. Attackers can return a CEL map literal fabricating a target with an attacker-chosen metadata.namespace, causing the privileged background controller to overwrite Secrets, Deployments, or policies cluster-wide.

CWE	CWE-862
Vendor	kyverno
Product	kyverno
Published	Nov 5, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

High

Affected Versions

kyverno / kyverno

1.17.0 < 1.19.2

References

NVD ↗ CVE.org ↗ EPSS Data ↗

github.com: https://github.com/kyverno/kyverno/security/advisories/GHSA-jcw5-3wcg-fqx5 vulncheck.com: https://www.vulncheck.com/advisories/kyverno-1.17.0-before-1.19.2-cross-namespace-resource-overwrite-via-namespacedmutatingpolicy

Credits

manus-pi manus-use