---
id: CVE-2026-114642
title: >-
  Traefik before 2.11.58 and 3.7.14 TLS Config Bypass via NTLM/Kerberos Round
  Tripper
summary: >-
  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 bac…
severity: high
cvss: 8.7
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N'
cvssSource: cna
cwe:
  - CWE-295
vendor: traefik
product: traefik
affected:
  - traefik >= 2.11.0 < 2.11.58
  - traefik >= 3.0.0 < 3.7.14
published: '2026-10-22'
updated: '2026-10-22'
sourceUpdated: '2026-10-22T01:43:41.355Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-114642'
references:
  - url: 'https://github.com/traefik/traefik/security/advisories/GHSA-cw35-4q88-3rmp'
    label: GitHub Security Advisory (GHSA-cw35-4q88-3rmp)
  - url: >-
      https://www.vulncheck.com/advisories/traefik-before-2.11.58-and-3.7.14-tls-config-bypass-via-ntlm-kerberos-round-tripper
    label: >-
      VulnCheck Advisory: Traefik before 2.11.58 and 3.7.14 TLS Config Bypass
      via NTLM/Kerberos Round Tripper
tags:
  - cve.org
ingestedAt: '2026-10-22T02:23:25.183Z'
---

## Overview

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.

## Affected

- `traefik >= 2.11.0 < 2.11.58`
- `traefik >= 3.0.0 < 3.7.14`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.