---
id: CVE-2026-122303
title: >-
  Kyverno 1.17.0 before 1.19.2 Cross-Namespace Resource Overwrite via
  NamespacedMutatingPolicy
summary: >-
  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. Att…
severity: critical
cvss: 9.9
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H'
cvssSource: cna
cwe:
  - CWE-862
vendor: kyverno
product: kyverno
affected:
  - kyverno >= 1.17.0 < 1.19.2
published: '2026-11-05'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T02:25:08.280Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-122303'
references:
  - url: 'https://github.com/kyverno/kyverno/security/advisories/GHSA-jcw5-3wcg-fqx5'
    label: GitHub Security Advisory (GHSA-jcw5-3wcg-fqx5)
  - url: >-
      https://www.vulncheck.com/advisories/kyverno-1.17.0-before-1.19.2-cross-namespace-resource-overwrite-via-namespacedmutatingpolicy
    label: >-
      VulnCheck Advisory: Kyverno 1.17.0 before 1.19.2 Cross-Namespace Resource
      Overwrite via NamespacedMutatingPolicy
tags:
  - cve.org
ingestedAt: '2026-11-05T21:36:00.683Z'
---

## Overview

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.

## Affected

- `kyverno >= 1.17.0 < 1.19.2`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.