What is CVE-2026-114640?

CVE-2026-114640 is a high-severity vulnerability in Traefik, classified under Authentication Bypass by Spoofing. CVSS score: 8.7/10. Published 2026-10-22.

How severe is CVE-2026-114640?

High severity. CVSS v3 base score is 8.7 out of 10.

Vulnerability in Traefik

CVE-2026-114640

Traefik from v3.7.0 before v3.7.14 contains an authentication bypass vulnerability in its Kubernetes Ingress-NGINX provider that forwards client-supplied Ssl-Client-* headers on the plaintext HTTP router. When ssl-redirect is disabled alongside auth-tls-pass-certificate-to-upstream, unauthenticated attackers can send Ssl-Client-Verify: SUCCESS with a chosen certificate subject and issuer to impersonate mTLS identities.

Published 2026-10-22 · last modified 2026-10-22.

CVSS v3 metric

CVSS v3 base score 8.7 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N.

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

Traefik

Weakness classification (CWE)

CWE-290 — Authentication Bypass by Spoofing

References

github.com/traefik/traefik/security/advisories/GHSA-mwrr-6hp4-pxr6 (vendor-advisory)
www.vulncheck.com/advisories/traefik-3.7.0-before-3.7.14-mtls-header-spoofing-v… (third-party-advisory)

Frequently asked questions

What is CVE-2026-114640?: CVE-2026-114640 is a high-severity vulnerability in Traefik, classified under Authentication Bypass by Spoofing. CVSS score: 8.7/10. Published 2026-10-22.
How severe is CVE-2026-114640?: High severity. CVSS v3 base score is 8.7 out of 10.