Vulnerability · Published Oct 22, 2026 · Assigned by VulnCheck

CVE-2026-114656Traefik before 2.11.58 and 3.7.13 mTLS Bypass via Negated Host Matcher

High 7.5

In plain English

A high-severity security flaw in traefik from traefik. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.2%top 95.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Traefik before 2.11.58 and 3.7.13 contains an authentication bypass vulnerability that allows unauthenticated clients to skip client-certificate checks because negated Host matchers are counted as served domains. Attackers can reach backends protected by RequireAndVerifyClientCert when a router rule with !Host() creates a TLS options conflict that falls back to the default options.

Affected products (as reported)

VendorProductVersions
traefik traefik 0 – before 2.11.58
traefik traefik 3.0.0 – before 3.7.13

Weakness: CWE-436 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N

References