Kyverno is widely deployed in Kubernetes clusters; this auth bypass lets tenant namespaces overwrite Secrets/Deployments cluster‑wide, risking broad cloud infra compromise.
CVE-2026-122303
Auth bypass lets namespace tenants overwrite resources across namespaces.
do firstUpgrade to a fixed release: 1.19.2.
Is CVE-2026-122303 being exploited?
Not confirmed. CVE-2026-122303 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.33% probability of exploitation in the next 30 days.
How severe is CVE-2026-122303?
CVE-2026-122303 is rated Critical with a CVSS score of 9.4. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-122303?
Yes. A fix has been recorded for CVE-2026-122303. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-122303 affect?
CVE-2026-122303 affects Kyverno 1.17.0 - <1.19.2, Kubernetes clusters running Kyverno, NamespacedMutatingPolicy (mutate-existing). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-122303?
Upgrade Kyverno to >=1.19.2 immediately; audit/restrict NamespacedMutatingPolicy and rotate exposed secrets.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Namespace tenants can trick the privileged Kyverno controller to overwrite Secrets, Deployments, and policies in other namespaces (cluster‑wide privilege escalation).
Immediate action required
- affected>= 1.17.0 and < 1.19.2
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.
timeline
- 5 Nov 2026Published
- 5 Nov 2026CVE record last updated · same day later
- 5 Nov 2026Analysed by vulneraibility.com · 1 day later
- Advisorygithub.com /kyverno/kyverno/security/advisories/GHSA-jcw5-3wcg-fqx5
- Advisoryvulncheck.com /advisories/kyverno-1.17.0-before-1.19.2-cross-namespace-resource-overwrite-via-
sources
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- FIRST EPSS: exploit probability and percentile
- Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.