Traefik: ForwardAuth trustForwardHeader=false allows spoofed X-Forwarded-Prefix to bypass auth
Priority MEDIUM 42CWE-345Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · None · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-345.
Summary
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00267 18th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed traefik (traefik): 2.11.43, 3.6.14, 3.7.0-rc.2github.com/traefik/traefik/v3 (Go): 3.7.0-rc.2, 3.6.14+1 more productRed Hat: 1 advisory
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| traefik | traefik | before 2.11.43; 3.0.0-beta1 to before 3.6.14; 3.7.0-ea.1 to before 3.7.0-rc.2 | 2.11.43, 3.6.14, 3.7.0-rc.2 | Patch available | CNA |
| — | github.com/traefik/traefik/v3 (Go) | 3.7.0-ea.1 to before 3.7.0-rc.2 | 3.7.0-rc.2 | Patch available | GHSA-6384-m2mw-rf54 |
| — | github.com/traefik/traefik/v3 (Go) | 3.0.0-beta1 to before 3.6.14 | 3.6.14 | Patch available | GHSA-6384-m2mw-rf54 |
| — | github.com/traefik/traefik/v2 (Go) | before 2.11.43 | 2.11.43 | Patch available | GHSA-6384-m2mw-rf54 |
| — | github.com/traefik/traefik (Go) | up to 1.7.34 | — | No fix listed | GHSA-6384-m2mw-rf54 |
- traefik Vendortraefik Affected before 2.11.43; 3.0.0-beta1 to before 3.6.14; 3.7.0-ea.1 to before 3.7.0-rc.2 Fixed in 2.11.43, 3.6.14, 3.7.0-rc.2 Patch available CNA
- github.com/traefik/traefik/v3 (Go) Vendor— Affected 3.7.0-ea.1 to before 3.7.0-rc.2 Fixed in 3.7.0-rc.2 Patch available GHSA-6384-m2mw-rf54
- github.com/traefik/traefik/v3 (Go) Vendor— Affected 3.0.0-beta1 to before 3.6.14 Fixed in 3.6.14 Patch available GHSA-6384-m2mw-rf54
- github.com/traefik/traefik/v2 (Go) Vendor— Affected before 2.11.43 Fixed in 2.11.43 Patch available GHSA-6384-m2mw-rf54
- github.com/traefik/traefik (Go) Vendor— Affected up to 1.7.34 Fixed in — No fix listed GHSA-6384-m2mw-rf54
CPE configurations NVD · 5
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:* | before 2.11.43; 3.0.0 to before 3.6.14 | Vulnerable | traefik |
| cpe:2.3:a:traefik:traefik:3.7.0:ea1:*:*:*:*:*:* | 3.7.0 ea1 | Vulnerable | traefik |
| cpe:2.3:a:traefik:traefik:3.7.0:ea2:*:*:*:*:*:* | 3.7.0 ea2 | Vulnerable | traefik |
| cpe:2.3:a:traefik:traefik:3.7.0:ea3:*:*:*:*:*:* | 3.7.0 ea3 | Vulnerable | traefik |
| cpe:2.3:a:traefik:traefik:3.7.0:rc1:*:*:*:*:*:* | 3.7.0 rc1 | Vulnerable | traefik |
- cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:* Versions before 2.11.43; 3.0.0 to before 3.6.14 Vulnerable ·traefik
- cpe:2.3:a:traefik:traefik:3.7.0:ea1:*:*:*:*:*:* Versions 3.7.0 ea1 Vulnerable ·traefik
- cpe:2.3:a:traefik:traefik:3.7.0:ea2:*:*:*:*:*:* Versions 3.7.0 ea2 Vulnerable ·traefik
- cpe:2.3:a:traefik:traefik:3.7.0:ea3:*:*:*:*:*:* Versions 3.7.0 ea3 Vulnerable ·traefik
- cpe:2.3:a:traefik:traefik:3.7.0:rc1:*:*:*:*:*:* Versions 3.7.0 rc1 Vulnerable ·traefik
Remediation
- Fix · CNA traefik (traefik) Fixed in 2.11.43, 3.6.14, 3.7.0-rc.2
- Fix · GHSA-6384-m2mw-rf54 github.com/traefik/traefik/v3 (Go) Fixed in 3.7.0-rc.2 Advisory →
- Fix · GHSA-6384-m2mw-rf54 github.com/traefik/traefik/v3 (Go) Fixed in 3.6.14 Advisory →
- Fix · GHSA-6384-m2mw-rf54 github.com/traefik/traefik/v2 (Go) Fixed in 2.11.43 Advisory →
Red Hat 1 advisory
- RHSA-2026:21772 Released 2026-05-28 · Red Hat rating ImportantRed Hat OpenShift Dev Spaces 3.28.0 Release.
- Red Hat OpenShift Dev Spaces 3.28 registry.redhat.io/devspaces/code-rhel9, registry.redhat.io/devspaces/dashboard-rhel9, registry.redhat.io/devspaces/openvsx-rhel9 +3
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat OpenShift Dev Spaces 3.28 | Fixed | RHSA-2026:21772 |
Not affected: 1 product
- Red Hat OpenShift Dev Spaces 3.28
Timeline
- 2026-10-02 Threatist record created from CVE-2026-35051
- 2026-10-03 Alias added: GHSA-6384-m2mw-rf54
References
More Traefik vulnerabilities
- TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
- TI-2023-25774 Uncontrolled Resource Consumption in Traefik CVSS 3.1HIGH 7.5
- TI-2025-40914 Traefik doesn't Prevent Path Normalization Bypass in Router + Middleware Rules CVSS 4.0MEDIUM 6.9
- TI-2022-07529 Authorization header displayed in the debug logs CVSS 3.1MEDIUM 6.5
- TI-2024-30459 HTTP client can remove the X-Forwarded headers in Traefik CVSS 3.1CRITICAL 9.8
- TI-2026-60261 Traefik v3.7.0 Authentication Bypass via from-to-www-redirect CVSS 4.0CRITICAL 9.3
Sources
- CVE-2026-35051 · CVE Program
- CVE-2026-35051 · NVD
- FIRST EPSS
- GHSA-6384-m2mw-rf54 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-35051 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences