CVE-2026-88007
Description
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.
How to fix
- traefik traefik2.11.56, 3.7.12 or later
- github.com/traefik/traefik/v33.7.13 or later
- github.com/traefik/traefik/v22.11.57 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| traefik traefik | 2.8.2 ≤ v < 2.11.56, 3.0.0 ≤ v < 3.7.12 | 2.11.56, 3.7.12 |
| github.com/traefik/traefik/v3Go | 3.0.0 ≤ v < 3.7.13 | 3.7.13 |
| github.com/traefik/traefik/v2Go | 2.11.0 ≤ v < 2.11.57 | 2.11.57 |
| github.com/traefik/traefikGo | No range specified | — |
Check your version
Choose the product and enter the version you run to see whether it falls in the affected range.
Attack Surface Management
See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.