Is CVE-2026-114640 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-114640 being exploited in the wild.

How severe is CVE-2026-114640?

High severity, with a CVSS score of 8.7, published 22 October 2026.

Which products and versions are affected?

Traefik Labs Traefik v3.7.0 through v3.7.13.

Is there a fix for CVE-2026-114640?

Yes: fixed in v3.7.14. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-114640 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-114640?

Check whether you run Traefik Labs Traefik at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-114640: Traefik Ingress-NGINX mTLS identity spoofing via forged headers

CVE-2026-114640 · Severity: high · CVSS 8.7 · Published 2026-10-22

Traefik is a reverse proxy and load balancer used to route traffic to services in Kubernetes clusters. When configured with the Ingress-NGINX provider and specific authentication settings, an unauthenticated attacker can forge SSL/TLS client identity headers to impersonate legitimate mTLS-authenticated clients, bypassing authentication controls. This allows an attacker to gain unauthorized access to backend services that trust these headers for access control.

Technologies: Traefik Labs Traefik. Vendors: Traefik Labs.

Quick answers

Is CVE-2026-114640 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-114640 being exploited in the wild.
How severe is CVE-2026-114640?: High severity, with a CVSS score of 8.7, published 22 October 2026.
Which products and versions are affected?: Traefik Labs Traefik v3.7.0 through v3.7.13.
Is there a fix for CVE-2026-114640?: Yes: fixed in v3.7.14. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-114640 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-114640?: Check whether you run Traefik Labs Traefik at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

Fixed in: v3.7.14

Technical details

The vulnerability exists in Traefik v3.7.0 through v3.7.13 when the Ingress-NGINX provider is used with both the auth-tls-pass-certificate-to-upstream annotation and ssl-redirect disabled. The middleware that validates and forwards Ssl-Client-* headers is only attached to the TLS router; the plaintext HTTP router forwards client-supplied headers without validation. An attacker sends Ssl-Client-Verify: SUCCESS with a forged certificate subject and issuer to spoof an mTLS identity. Attack vector is network-based with no authentication or user interaction required.

Affected products

Traefik Labs Traefik v3.7.0 through v3.7.13

Timeline

2026-10-07: disclosed
2026-10-21: advisory
2026-10-22: patched

References

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