CVE-2026-114656GHSA-2272-4vv8-65ww
Traefik before 2.11.58 and 3.7.13 mTLS Bypass via Negated Host Matcher
traefik traefik
CVSS
6.9MediumExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.16%Chance of exploitation activity in the next 30 days, higher than 5% of CVEs. Scored 23 Oct 2026FIRST EPSS
What fixes it
A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.
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.
Text from CVE List
Affected versions 4
- traefikaffected: all versions before 2.11.58CVE List
- traefikunaffected: 2.11.58CVE List
- traefikaffected: 3.0.0 before 3.7.13CVE List
- traefikunaffected: 3.7.13CVE List