high
CVE-2026-121966
Traefik ForwardAuth shares one auth-server connection pool across all clients - with an NTLM/Negotiate (connection-bound) auth server, an unauthenticated client's subrequest rides a connection already authenticated as another user, and authResponseHeaders forwards that user's identity to the backend (CVSS 7.0)
- Severity
- high
- Affected product
- Traefik
- Affected versions
- Traefik ≥ 2.0.0, < 2.11.60
- Affected versions
- Traefik ≥ 3.0.0, < 3.7.16
- Fixed in
- Traefik 2.11.60
- Fixed in
- Traefik 3.7.16
- Detection basis
- Appliance fingerprint
- Shipped rule
- Traefik: Traefik ForwardAuth shares one auth-server connection pool across all clients - with an NTLM/Negotiate (connection-bound) auth server, an unauthenticated client's subrequest rides a connection already authenticated as another user, and authResponseHeaders forwards that user's identity to the backend (CVSS 7.0)
- Added to NewScan
- 2026-11-05
- 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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