medium
CVE-2026-88011
Traefik ForwardAuth identity spoofing via a dot-form header alias - the client supplies X.Authenticated.User alongside the canonical X-Authenticated-User that ForwardAuth writes, and Go's lexical header ordering makes the attacker's value win at the backend (CVSS 5.3)
- Severity
- medium
- Affected product
- Traefik
- Affected versions
- Traefik ≥ 2.0.0, < 2.11.56
- Affected versions
- Traefik ≥ 3.0.0, < 3.7.12
- Fixed in
- Traefik 2.11.56
- Fixed in
- Traefik 3.7.12
- Detection basis
- Appliance fingerprint
- Shipped rule
- Traefik: Traefik ForwardAuth identity spoofing via a dot-form header alias - the client supplies X.Authenticated.User alongside the canonical X-Authenticated-User that ForwardAuth writes, and Go's lexical header ordering makes the attacker's value win at the backend (CVSS 5.3)
- Added to NewScan
- 2026-09-11
- Detected by
- NewScan — free, self-hosted
How NewScan reports it
APPLIANCE FINGERPRINT
NewScan fingerprints the Traefik appliance and reports this CVE when the detected version falls inside the affected range below.
APPLIANCE FINGERPRINT
NewScan fingerprints the Traefik appliance and reports this CVE when the detected version falls inside the affected range below.
References
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