Traefik is an open source HTTP reverse proxy and load balancer. From 2.11.0 until 2.11.57 and 3.7.13, the HTTP/3 entrypoint ConnContext does not call service.AddTransportOnContext, so kerberosRoundTripper uses a shared backend transport instead of a transport dedicated to each frontend connection. With HTTP/3 enabled, a backend using connection-bound NTLM or Negotiate authentication, and backend keep-alive, an unrelated client can reuse a backend connection authenticated for a victim, read victim-only data, and act as that victim without the victim credentials. This issue is fixed in 2.11.57 and 3.7.13.
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Traefik | Traefik | 2.8.2 (including) | 2.11.56 (excluding) |
| Traefik | Traefik | 3.0.0 (including) | 3.7.12 (excluding) |