CVE-2026-88007
criticalTraefik is an open source HTTP reverse proxy and load balancer.
Vendor / product: Traefik — traefik
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N Affected products
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
References
- https://github.com/traefik/traefik/commit/ff39c47d7459dec9cd8de63c1a4e7aa7315bdc1c security-advisories@github.com
- https://github.com/traefik/traefik/pull/13812 security-advisories@github.com
- https://github.com/traefik/traefik/releases/tag/v2.11.57 security-advisories@github.com
- https://github.com/traefik/traefik/releases/tag/v3.7.13 security-advisories@github.com
- https://github.com/traefik/traefik/security/advisories/GHSA-qqjf-53cj-pwvv security-advisories@github.com