critical10.0
CVE-2026-35051
Traefik's ForwardAuth trustForwardHeader=false allows spoofed X-Forwarded-Prefix to bypass authentication
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| go | github.com/traefik/traefik/v3 | >= 3.7.0-ea.1, < 3.7.0-rc.2 | 3.7.0-rc.2 |
| go | github.com/traefik/traefik/v2 | < 2.11.43 | 2.11.43 |
| go | github.com/traefik/traefik | <= 1.7.34 | none recorded |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Traefik | Traefik | before 2.11.43 from 3.0.0 before 3.6.14 Version 3.7.0 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-6384-m2mw-rf54
- https://github.com/traefik/traefik/security/advisories/GHSA-6384-m2mw-rf54
- https://github.com/traefik/traefik/releases/tag/v2.11.43
- https://github.com/traefik/traefik/releases/tag/v3.6.14
- https://github.com/traefik/traefik/releases/tag/v3.7.0-rc.2
- https://nvd.nist.gov/vuln/detail/CVE-2026-35051
- https://access.redhat.com/errata/RHSA-2026:21772
- https://access.redhat.com/security/cve/CVE-2026-35051
- https://bugzilla.redhat.com/show_bug.cgi?id=2464235
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-35051.json