Vulnerability in Kyverno

CVE-2026-100706

kyverno before 1.19.1 fails to properly validate URL-encoded path segments in Policy apiCall urlPath, allowing namespace tenants to bypass the per-namespace clamp and create objects in other namespaces as the admission-controller ServiceAccount. Attackers can exploit this by using percent-encoded directory traversal sequences to create MutatingWebhookConfiguration objects cluster-wide or PolicyException objects in the kyverno namespace, enabling privilege escalation to cluster admin.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-100706?
CVE-2026-100706 is a critical-severity vulnerability in Kyverno, classified under Unintended Proxy or Intermediary (Confused Deputy). CVSS score: 9.9/10. Published 2026-09-26.
How severe is CVE-2026-100706?
Critical severity. CVSS v3 base score is 9.9 out of 10.