CVE-2026-114639

Traefik 2.11.0 before 2.11.58 and 3.0.0 before 3.7.14 contains an authentication bypass because a first request preauthenticated with an Authorization: Negotiate token authenticates a socket in the globally shared backend connection pool, which is never isolated. Unauthenticated attackers on separate frontend connections can be assigned that NTLM/Kerberos-bound socket and perform reads or writes with the victim's identity.

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-qm9f-w54v-q2qh	Vendor Advisory
https://www.vulncheck.com/advisories/traefik-before-2.11.58-and-3.7.14-authentication-bypass-via-negotiate-connection-pool	Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

27 Oct 2026, 14:17

Type	Values Removed	Values Added
CPE		cpe:2.3:a:traefik:traefik::::::::
First Time		Traefik Traefik traefik
References	~~() https://github.com/traefik/traefik/security/advisories/GHSA-qm9f-w54v-q2qh -~~	() https://github.com/traefik/traefik/security/advisories/GHSA-qm9f-w54v-q2qh - Vendor Advisory
References	~~() https://www.vulncheck.com/advisories/traefik-before-2.11.58-and-3.7.14-authentication-bypass-via-negotiate-connection-pool -~~	() https://www.vulncheck.com/advisories/traefik-before-2.11.58-and-3.7.14-authentication-bypass-via-negotiate-connection-pool - 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 14:17

NVD link : CVE-2026-114639

Mitre link : CVE-2026-114639

CVE.ORG link : CVE-2026-114639

JSON object : View

Products Affected

traefik

traefik

CWE

CWE-287

Improper Authentication

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