All vulnerabilities
CVE-2026-114642GHSA-cw35-4q88-3rmp

Traefik before 2.11.58 and 3.7.14 TLS Config Bypass via NTLM/Kerberos Round Tripper

traefik traefik
Open in ThreatlineRecord JSON
CVSS
7.0High
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.17%Chance of exploitation activity in the next 30 days, higher than 5% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in2.11.58Also 3.7.14CVE List
Published22 Oct 2026Updated 23 Oct 2026CVE List

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 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.

Text from CVE List

Affected versions 4

  • traefikaffected: 2.11.0 before 2.11.58CVE List
  • traefikunaffected: 2.11.58CVE List
  • traefikaffected: 3.0.0 before 3.7.14CVE List
  • traefikunaffected: 3.7.14CVE List

References 2