critical
CVE-2026-88877
Traefik Kubernetes Ingress NGINX provider authentication bypass - an Ingress carrying both an auth annotation and from-to-www-redirect generates a sibling host-only router that reaches the protected backend with NO annotation-derived middleware, so a non-numeric port in the Host header (`Host: www.example.com:x`) discards BasicAuth and source-IP allowlisting alike (CVSS 9.3)
- Severity
- critical
- Affected product
- Traefik
- Affected versions
- Traefik ≥ 3.7.0, < 3.7.12
- Fixed in
- Traefik 3.7.12
- Detection basis
- Appliance fingerprint
- Shipped rule
- Traefik: Traefik Kubernetes Ingress NGINX provider authentication bypass - an Ingress carrying both an auth annotation and from-to-www-redirect generates a sibling host-only router that reaches the protected backend with NO annotation-derived middleware, so a non-numeric port in the Host header (`Host: www.example.com:x`) discards BasicAuth and source-IP allowlisting alike (CVSS 9.3)
- 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.
References
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