CVE-2026-85596

Traefik versions >= v3.7.0 and <= v3.7.10 contain an authentication bypass in the Kubernetes Ingress NGINX provider. The TLS option generated for an Ingress carrying the nginx.ingress.kubernetes.io/auth-tls-secret annotation was named after the Ingress namespace and name. As a result, two Ingress objects sharing the same host, the same client CA secret, and the same client-authentication mode produced two distinct TLS option names for that host. Traefik treats this as a TLS options conflict and falls back to the entry point's default TLS configuration, which does not request a client certificate, so a route configured with nginx.ingress.kubernetes.io/auth-tls-verify-client: "on" becomes reachable without a client certificate. Only the v3.7 line is affected; the issue is fixed in v3.7.11.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/traefik/traefik/security/advisories/GHSA-j994-9gqj-9hwq	Exploit Mitigation Patch Vendor Advisory
https://www.vulncheck.com/advisories/traefik-3.7-authentication-bypass-via-tls-option-conflict	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*

History

16 Sep 2026, 20:42

Type	Values Removed	Values Added
First Time		Traefik Traefik traefik
References	~~() https://github.com/traefik/traefik/security/advisories/GHSA-j994-9gqj-9hwq -~~	() https://github.com/traefik/traefik/security/advisories/GHSA-j994-9gqj-9hwq - Exploit, Mitigation, Patch, Vendor Advisory
References	~~() https://www.vulncheck.com/advisories/traefik-3.7-authentication-bypass-via-tls-option-conflict -~~	() https://www.vulncheck.com/advisories/traefik-3.7-authentication-bypass-via-tls-option-conflict - Third Party Advisory
CPE		cpe:2.3:a:traefik:traefik::::::::
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.8

Information

Published : 2026-09-04 12:17

Updated : 2026-10-08 16:17

NVD link : CVE-2026-85596

Mitre link : CVE-2026-85596

CVE.ORG link : CVE-2026-85596

JSON object : View

Products Affected

traefik

traefik

CWE

CWE-287

Improper Authentication

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