원문 설명
Traefik is an HTTP reverse proxy and load balancer. In Traefik v1.x, v2.x through v2.11.55, and v3.0.0 through v3.7.11, header names are canonicalized only on dashes, so X-Auth-User, X_Auth_User and X.Auth.User are treated as three distinct headers by Traefik, while backends that derive variable names from header names (CGI, WSGI, PHP, NGINX and others) collapse them into a single variable. A client can therefore smuggle a dot-form alias of a header that Traefik manages past the middleware managing it — for example supplying X.Authenticated.User alongside the canonical X-Authenticated-User written by the ForwardAuth middleware — causing such a backend to read the client-supplied value instead of the identity Traefik asserted. In the tested configuration (PHP 8.2 built-in SAPI over an HTTP/1 backend path), Go's lexical header ordering makes the attacker-supplied value win deterministically, so a client that ForwardAuth admits as a low-privilege identity can be treated by the backend as a different user or role. Any header Traefik sets is affected, not only ForwardAuth's. This is an incomplete fix for GHSA-x677-9fxg-v5c5, which blocked only the underscore form. Fixed in v2.11.56 and v3.7.12, which add the aliasHeadersStrategy entry-point option; because it defaults to 'keep' for backwards compatibility, it must be explicitly set to 'delete' or 'reject' for the fix to take effect. Unmaintained release lines will not receive a patch.
영향받는 소프트웨어
- Traefik *≥ 3.0.0 < 3.7.12< 2.11.56≥ 1.0 < 2.11.56≥ 3.0.0 ≤ 3.7.13 수정 버전: 3.7.12, 2.11.56 저장소·패키지 일치
상세
- 공개일
- 2026-09-10
- 최종 수정
- 2026-10-09
- CVSS 벡터
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N- CWE
- CWE-290
참고 자료
내 서버의 버전을 직접 추적하세요
InfraGuard 는 모든 서버에 설치된 소프트웨어 버전을 수집하고, 알려진 취약점이 있는 버전을 알려 줍니다. 자체 호스팅이라 데이터가 내 네트워크를 벗어나지 않습니다.
이 제품은 NVD API 데이터를 사용하지만 NVD 의 보증이나 인증을 받은 것은 아닙니다. CVE® 는 The MITRE Corporation 의 등록 상표이며, CVE 레코드는 CVE Program 이용 약관에 따라 사용합니다.