CVE-2026-54764

[CVE catalog]

Severity

Medium · CVSS 6.9

Published

Jul 6, 2026, 8:20:29 PM UTC

Source

[NVD] · [CVE record]

EPSS

0.28% · Oct 25, 2026

A flaw was found in Traefik, an HTTP reverse proxy and load balancer. The ForwardAuth middleware, even when configured to not trust forwarded headers, incorrectly uses the original incoming request to determine the X-Forwarded-Port header sent to the authentication service. This allows an unauthenticated remote attacker to inject a false X-Forwarded-Proto: https header over a plain HTTP connection, leading Traefik to forward X-Forwarded-Port: 443 to the authentication service. This bypasses port-based authorization checks, potentially granting unauthorized access. traefik: Traefik: Authorization bypass in ForwardAuth middleware via forged X-Forwarded-Port Moderate: A flaw in Traefik's ForwardAuth middleware, as used in Red Hat OpenShift Dev Spaces, allows an unauthenticated remote attacker to bypass port-based authorization. By injecting a forged `X-Forwarded-Proto` header over an HTTP connection, an attacker can cause the authentication service to receive an incorrect `X-Forwarded-Port` value, leading to unauthorized access. The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.