CVE-2026-85596
Description
A flaw was found in Traefik. This vulnerability allows a remote attacker to bypass authentication, gaining unauthorized access to protected routes. This occurs due to a conflict in how Traefik handles Transport Layer Security (TLS) options when specific Kubernetes Ingress objects are configured. The conflict causes Traefik to use a less secure default configuration, negating the requirement for client certificates.
Statement
A flaw was found in Traefik's Kubernetes Ingress NGINX provider (v3.7.0 through v3.7.10) where TLS options generated for Ingress objects using the auth-tls-secret annotation are incorrectly named using the namespace and Ingress name. When multiple Ingress objects share the same host, client CA secret, and authentication mode, Traefik misinterprets the resulting distinct TLS option names as a configuration conflict. This causes Traefik to regress to default entrypoint TLS options that do not request client certificates, allowing remote unauthenticated attackers to bypass mTLS requirements on routes protected by auth-tls-verify-client.
Mitigation
Consolidate Ingress rules sharing the same host and client CA secret into a single Ingress resource, or avoid using the auth-tls-secret annotation across multiple distinct Ingress objects for a shared host. Alternatively, enforce client certificate validation at an upstream load balancer or API gateway until patched.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | N/A | N/A |
| Attack Vector | Network | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | None | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | High | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | None | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Understanding the Weakness (CWE)
Access Control
Technical Impact: Bypass Protection Mechanism
Frequently Asked Questions
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