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.
- Score
- CVSS 3.1 9.8 Critical
- Status
- Analyzed - disclosure@vulncheck.com
- Published
- 2026-09-04
- Last modified
- 2026-10-08
- Weaknesses
- CWE-287
Affected products
References
- https://github.com/traefik/traefik/security/advisories/GHSA-j994-9gqj-9hwq
- https://www.vulncheck.com/advisories/traefik-3.7-authentication-bypass-via-tls-option-conflict
