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.

CVSS v3 8.7 HIGH

8.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.8

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope CHANGED

References

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

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:traefik:traefik::::::::
	cpe:2.3:a:traefik:traefik::::::::

History

27 Oct 2026, 14:13

Type	Values Removed	Values Added
First Time		Traefik Traefik traefik
CPE		cpe:2.3:a:traefik:traefik::::::::
References	~~() https://github.com/traefik/traefik/security/advisories/GHSA-cw35-4q88-3rmp -~~	() https://github.com/traefik/traefik/security/advisories/GHSA-cw35-4q88-3rmp - Vendor Advisory
References	~~() https://www.vulncheck.com/advisories/traefik-before-2.11.58-and-3.7.14-tls-config-bypass-via-ntlm-kerberos-round-tripper -~~	() https://www.vulncheck.com/advisories/traefik-before-2.11.58-and-3.7.14-tls-config-bypass-via-ntlm-kerberos-round-tripper - Third Party Advisory

22 Oct 2026, 02:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-22 02:16

Updated : 2026-10-27 14:13

NVD link : CVE-2026-114642

Mitre link : CVE-2026-114642

CVE.ORG link : CVE-2026-114642

JSON object : View

Products Affected

traefik

traefik

CWE

CWE-295

Improper Certificate Validation

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