Vulnerability in Traefik
CVE-2026-114642
Traefik 2.11.0 before 2.11.58 and 3.0.0 before 3.7.14 stores its NTLM/Kerberos backend round tripper in a client-connection slot not keyed by ServersTransport, so one service's TLS client configuration is reused for another service's backend. An unauthenticated client can arm the slot via a backend issuing an NTLM or Negotiate challenge, then reach another service on the same keep-alive connection, bypassing its root CAs, server name, and certificate verification.
Vulnerability class: Improper Certificate Validation
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.7 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/traefik/traefik/security/advisories/GHSA-cw35-4q88-3rmp (vendor-advisory)
- www.vulncheck.com/advisories/traefik-before-2.11.58-and-3.7.14-tls-config-bypas… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-114642?
- CVE-2026-114642 is a high-severity vulnerability in Traefik, classified under Improper Certificate Validation. CVSS score: 8.7/10. Published 2026-10-22.
- How severe is CVE-2026-114642?
- High severity. CVSS v3 base score is 8.7 out of 10.