CVE-2026-100706CWE-441

CVE-2026-100706

Critical · published September 26, 2026

CVSS v3.1
9.9
EPSS
1%
Percentile
48.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.9 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CVSS v4.0
9.4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
EPSS
0.00613 · 48.7th percentile
Weakness
CWE-441 · Unintended Proxy or Intermediary ('Confused Deputy')
Published
2026-09-26T18:16Z
References (2)
https://github.com/kyverno/kyverno/security/advisories/GHSA-5qq8-67g6-4h2w · [email protected]https://www.vulncheck.com/advisories/kyverno-before-1.19.1-privilege-escalation-via-policy-apicall-urlpath · [email protected]
EPSS history
Timeline
  • 28 SEP 03:25Z
    EPSS moved — → 1%
    epss
  • 26 SEP 13:24Z
    kyverno before 1.19.1 Privilege Escalation via Policy apiCall urlPath
    cvelistv5