Description
Traefik is an HTTP reverse proxy and load balancer. Prior to v2.11.51, v3.6.22, and v3.7.6, Traefik's 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. As a result, an unauthenticated remote attacker can 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. This issue is fixed in versions v2.11.51, v3.6.22, and v3.7.6.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| traefik | traefik | < 2.11.51, >= 3.0.0, < 3.6.22, >= 3.7.0, < 3.7.6 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | govulncheck-vulndb | 0.0.20260827T195228-160000.1.1 | SUSE-SU-2026:23625-1 |
| SLES 16.0 | govulncheck-vulndb | 0.0.20260827T195228-160000.1.1 | SUSE-SU-2026:23625-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | traefik | 3.7.7-1.1 | openSUSE-SU-2026:11251-1 |
| openSUSE Tumbleweed | traefik2 | 2.11.52-1.1 | openSUSE-SU-2026:11243-1 |
| openSUSE Leap 16.0 | govulncheck-vulndb | 0.0.20260827T195228-160000.1.1 | openSUSE-SU-2026:21761-1 |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Go | github.com/traefik/traefik | <= 1.7.34 | — | GHSA-3q9r-p662-5j8m |
| Go | github.com/traefik/traefik | all versions | — | GO-2026-6202 |
| Go | github.com/traefik/traefik/v2 | < 2.11.51 | 2.11.51 | GHSA-3q9r-p662-5j8m |
| Go | github.com/traefik/traefik/v3 | < 3.6.22 | 3.6.22 | GHSA-3q9r-p662-5j8m |
| Go | github.com/traefik/traefik/v3 | >= 3.7.0, < 3.7.6 | 3.7.6 | GHSA-3q9r-p662-5j8m |
| Go | github.com/traefik/traefik/v3 | < 3.6.22 · >= 3.7.0, < 3.7.6 | 3.6.22, 3.7.6 | GO-2026-6202 |
Advisories 4
- SUSE-SU-2026:23625-1 Security update for govulncheck-vulndb SUSE / openSUSE Security Updates · Sep 29, 2026
- openSUSE-SU-2026:21761-1 Security update for govulncheck-vulndb SUSE / openSUSE Security Updates · Sep 9, 2026
- openSUSE-SU-2026:11251-1 traefik-3.7.7-1.1 on GA media SUSE / openSUSE Security Updates · Jul 11, 2026
- openSUSE-SU-2026:11243-1 traefik2-2.11.52-1.1 on GA media SUSE / openSUSE Security Updates · Jul 10, 2026