CVE-2026-71324

Description

Traefik is an open source HTTP reverse proxy and load balancer. Prior to 2.11.53, 3.6.24, and 3.7.9, Traefik's default HTTP reverse proxy forwards a plain HTTP/2 or HTTP/3 CONNECT request and its body to an HTTP/1.1 upstream through a shared net/http.Transport. When the upstream answers the CONNECT with a keep-alive non-2xx response and does not drain the body, Traefik returns the desynchronized backend socket to its shared pool and reuses it for other clients. An unauthenticated attacker can use this behavior to make a different client read the attacker's smuggled response, which can include authenticated or private content from another request. The ForwardAuth middleware with forwardBody true and preserveRequestMethod true can re-issue a CONNECT with the buffered body attached, exposing the auth-client pool to the same desynchronization. This issue is fixed in 2.11.53, 3.6.24, and 3.7.9.

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Produits concernés

• traefik
• Traefik traefik

Scores CVSS

Faiblesses (CWE)

• CWE-444

Références

• https://github.com/traefik/traefik/commit/04d36f28e4eae7535e96a6351dd9f7bfb48a30e7 Patch
• https://github.com/traefik/traefik/commit/0807b6d5dd1da8b2f7f4076ea2392b5437bf2ab0 Patch
• https://github.com/traefik/traefik/commit/94a7508817d180f0ab2f1eae93df48d4ab19ecce Patch
• https://github.com/traefik/traefik/pull/13542 Issue TrackingPatch
• https://github.com/traefik/traefik/pull/13543 Issue TrackingPatch
• https://github.com/traefik/traefik/pull/13556 Issue TrackingPatch
• https://github.com/traefik/traefik/releases/tag/v2.11.53 Release Notes
• https://github.com/traefik/traefik/releases/tag/v3.6.24 Release Notes
• https://github.com/traefik/traefik/releases/tag/v3.7.9 Release Notes
• https://github.com/traefik/traefik/security/advisories/GHSA-3ccp-42pg-hgv6 PatchVendor Advisory

Ailleurs

• NVD
• CVE.org
• CIRCL Vulnerability-Lookup
• CERT-FR
• GitHub Advisories