CVE-2026-35051CWE-345

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

High · published April 30, 2026

CVSS v4.0
7.8
EPSS
0%
Percentile
22.5
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
7.8 · HIGH
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:L/SA:N
EPSS
0.00309 · 22.5th percentile
Weakness
CWE-345 · Insufficient Verification of Data Authenticity
Published
2026-04-30T20:26Z
EPSS history
Timeline
  • 30 APR 20:26Z
    Traefik: ForwardAuth trustForwardHeader=false allows spoofed X-Forwarded-Prefix to bypass auth
    cvelistv5