CVE-2026-85596 (GCVE-0-2026-85596)

Vulnerability from cvelistv5 – Published: 2026-09-04 11:30 – Updated: 2026-09-10 15:09
VLAI
Title
Traefik v3.7 Authentication Bypass via TLS Option Conflict
Summary
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.
Severity
8.2 (High)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-10 14:19 UTC
CWE
  • CWE-287 - Improper Authentication
Assigner
References
Impacted products
Vendor Product Version
traefik traefik Affected: 3.7.0 , ≤ 3.7.10 (semver)
    cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-21 00:00
Credits
james-yusuke
Show details on NVD website
To clipboard 

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