CVE-2026-54764 traefik CVE debrief

Who should care

Users of Traefik who rely on the ForwardAuth middleware for authorization should be aware of this vulnerability and take steps to mitigate it. Operators, platform administrators, vulnerability management teams, and security teams may be impacted.

Technical summary

The Traefik ForwardAuth middleware, even when configured with trustForwardHeader: false, derives the X-Forwarded-Port header sent to the authentication service from the original incoming request instead of the sanitized forwarded request. This allows an unauthenticated remote attacker to inject an X-Forwarded-Proto: https header over a plain HTTP connection and cause Traefik to forward X-Forwarded-Port: 443 to the authentication service, bypassing port-based authorization checks.

Defensive priority

High

Recommended defensive actions

• Upgrade to Traefik version v2.11.51, v3.6.22, or v3.7.6 or later
• Verify and restrict the X-Forwarded-Port header in your authentication service
• Monitor and review authentication service logs for suspicious activity
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record was published on 2026-07-06T21:16:56.930Z and has been modified since then. The NVD entry is currently Undergoing Analysis. Evidence is limited, and defenders should verify affected scope and vendor guidance.

Official resources