CVE-2026-35051

CRITICAL

Traefik: ForwardAuth trustForwardHeader=false allows spoofed X-Forwarded-Prefix to bypass auth

Title source: cna
STIX 2.1

Description

Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.43, 3.6.14, and 3.7.0-rc.2, there is an authentication bypass vulnerability in Traefik's ForwardAuth middleware when trustForwardHeader=false is configured and Traefik is deployed behind a trusted upstream proxy. This issue has been patched in versions 2.11.43, 3.6.14, and 3.7.0-rc.2.

References (4)

Core 4
Core References

Scores

CVSS v3 10.0
EPSS 0.0026
EPSS Percentile 16.6%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact total

Details

CWE
CWE-345
Status published
Products (8)
traefik/traefik 3.7.0 ea1 (4 CPE variants)
traefik/traefik < 2.11.43 (2 CPE variants)
traefik/traefik 0 - 1.7.34Go
traefik/traefik 0 - 2.11.43Go
traefik/traefik 3.0.0-beta1 - 3.6.14Go
traefik/traefik 3.7.0-ea.1 - 3.7.0-rc.2Go
traefik/traefik >= 3.0.0-beta1, < 3.6.14
traefik/traefik >= 3.7.0-ea.1, < 3.7.0-rc.2
Published Apr 30, 2026
Tracked Since May 01, 2026