CVE-2026-114640 Traefik v3.7.0 before v3.7.14 mTLS Header Spoofing via Ingress-NGINX HTTP Router

What is CVE-2026-114640?

CVE-2026-114640 is a high-severity vulnerability in Traefik Traefik, published on 22 Oct 2026.

Official description

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.

Weakness: CWE-290

Which versions are affected by CVE-2026-114640?

It affects 1 product.

Products include Traefik Traefik.

How do I fix CVE-2026-114640?

Upgrade to a fixed version.

Is CVE-2026-114640 being exploited?

There is no known exploitation of CVE-2026-114640 in the wild and no public exploit code.

Other vulnerabilities in Traefik Traefik

• CVE-2024-45410 HTTP client can remove the X-Forwarded headers in Traefik Critical 9.8
• CVE-2026-88877 Traefik v3.7.0 Authentication Bypass via from-to-www-redirect Critical 9.3
• CVE-2026-85595 Traefik before v2.11.55 and v3.0.0 through v3.7.10 Authentication Bypass via digestAuth Critical 9.3
• CVE-2026-88007 Traefik HTTP/3 Backend NTLM Connection Reuse Critical 9.1
• CVE-2026-88009 Traefik: Rootless HTTP/1 request-target routes as "/" but is forwarded verbatim, bypassing path-scoped routing, middleware guards and access logging High 8.8

All Traefik Traefik vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• GitHub advisory
• How this page is made

Also known as GHSA-mwrr-6hp4-pxr6, GHSA-wwwm-2fq8-c2gm.