CVE-2026-114637

Traefik from v3.2.0 before v3.7.14 contains an authentication bypass vulnerability in the experimental FastProxy connection pool, which fails to pin NTLM/Negotiate-authenticated backend connections to their frontend connection. Unauthenticated clients can be handed a pooled keep-alive backend connection where a victim completed an NTLM or Negotiate handshake, letting them read victim data and act as that victim.

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-53qr-784g-cj35	Vendor Advisory
https://www.vulncheck.com/advisories/traefik-3.2.0-before-3.7.14-fastproxy-ntlm-negotiate-connection-pool-identity-leak	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*

History

27 Oct 2026, 14:17

Type	Values Removed	Values Added
References	~~() https://github.com/traefik/traefik/security/advisories/GHSA-53qr-784g-cj35 -~~	() https://github.com/traefik/traefik/security/advisories/GHSA-53qr-784g-cj35 - Vendor Advisory
References	~~() https://www.vulncheck.com/advisories/traefik-3.2.0-before-3.7.14-fastproxy-ntlm-negotiate-connection-pool-identity-leak -~~	() https://www.vulncheck.com/advisories/traefik-3.2.0-before-3.7.14-fastproxy-ntlm-negotiate-connection-pool-identity-leak - Third Party Advisory
First Time		Traefik Traefik traefik
CPE		cpe:2.3:a:traefik:traefik::::::::

22 Oct 2026, 02:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-22 02:16

Updated : 2026-10-28 19:17

NVD link : CVE-2026-114637

Mitre link : CVE-2026-114637

CVE.ORG link : CVE-2026-114637

JSON object : View

Products Affected

traefik

traefik

CWE

CWE-488

Exposure of Data Element to Wrong Session

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