CVE-2026-88004

Traefik is an open source HTTP reverse proxy and load balancer. From 3.2.0 until 3.7.13, Traefik entrypoint defenses aliasHeadersStrategy, underscoreHeadersStrategy, and forwardedHeaders inspect req.Header but not req.Trailer, allowing an unauthenticated client to submit an aliasing or trusted...

CVE-2026-88009 Traefik: Rootless HTTP/1 request-target routes as "/" but is forwarded verbatim, bypassing path-scoped routing, middleware guards and access logging

Traefik is an open source HTTP reverse proxy and load balancer. Prior to 2.11.57, and 3.7.13, Traefik accepts a rootless HTTP/1 request target that Go stores in URL.Opaque while leaving URL.Path empty. The rewriteRequestBuilder path evaluates routing, path sanitization, forwardAuth,...

EUVD-2026-75578

Traefik is an open source HTTP reverse proxy and load balancer. Prior to 2.11.57, and 3.7.13, Traefik accepts a rootless HTTP/1 request target that Go stores in URL.Opaque while leaving URL.Path empty. The rewriteRequestBuilder path evaluates routing, path sanitization, forwardAuth,...

EUVD-2026-75545

Traefik is an open source HTTP reverse proxy and load balancer. From 2.11.26 until 2.11.57 and 3.7.13, Traefik forwards a client-supplied Connection header requesting Upgrade, the Upgrade: h2c token, and HTTP2-Settings to a shared backend. If the backend accepts h2c and returns 101 Switching...

CVE-2026-88008 Traefik: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') and Incorrect Authorization

Traefik is an open source HTTP reverse proxy and load balancer. From 2.11.26 until 2.11.57 and 3.7.13, Traefik forwards a client-supplied Connection header requesting Upgrade, the Upgrade: h2c token, and HTTP2-Settings to a shared backend. If the backend accepts h2c and returns 101 Switching...

CVE-2026-88008

Traefik (open-source HTTP reverse proxy and load balancer) is vulnerable to a middleware bypass via unrestricted client-initiated Upgrade: h2c forwarding. Versions 2.11.26–2.11.56 , 3.7.0–3.7.12 , and EOL 3.4.2–3.6 are affected. When a shared backend accepts the h2c upgrade and returns 101 Switch...

CVE-2026-88008 Traefik: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') and Incorrect Authorization

Traefik is an open source HTTP reverse proxy and load balancer. From 2.11.26 until 2.11.57 and 3.7.13, Traefik forwards a client-supplied Connection header requesting Upgrade, the Upgrade: h2c token, and HTTP2-Settings to a shared backend. If the backend accepts h2c and returns 101 Switching...

CVE-2026-88007

Traefik versions 2.11.0 through 2.11.57 and 3.7.13 contain a backend connection reuse flaw in the HTTP/3 entrypoint. The ConnContext does not call service.AddTransportOnContext, causing kerberosRoundTripper to share a single backend transport across all frontend connections rather than using a de...

EUVD-2026-75538

Traefik is an open source HTTP reverse proxy and load balancer. From 3.2.0 until 3.7.13, Traefik entrypoint defenses aliasHeadersStrategy, underscoreHeadersStrategy, and forwardedHeaders inspect req.Header but not req.Trailer, allowing an unauthenticated client to submit an aliasing or trusted...

CVE-2026-88004

Traefik (open source HTTP reverse proxy and load balancer) versions 3.2.0 through 3.7.12 have a header sanitization bypass. The entrypoint defenses aliasHeadersStrategy , underscoreHeadersStrategy , and forwardedHeaders inspect only req.Header but not req.Trailer. An unauthenticated client can pl...

CVE-2026-88004

Traefik is an open source HTTP reverse proxy and load balancer. From 3.2.0 until 3.7.13, Traefik entrypoint defenses aliasHeadersStrategy, underscoreHeadersStrategy, and forwardedHeaders inspect req.Header but not req.Trailer, allowing an unauthenticated client to submit an aliasing or trusted...

CVE-2026-88004 Traefik entrypoint header-name sanitization bypassed via request trailers

Traefik is an open source HTTP reverse proxy and load balancer. From 3.2.0 until 3.7.13, Traefik entrypoint defenses aliasHeadersStrategy, underscoreHeadersStrategy, and forwardedHeaders inspect req.Header but not req.Trailer, allowing an unauthenticated client to submit an aliasing or trusted...

CVE-2026-88004 Traefik entrypoint header-name sanitization bypassed via request trailers

Traefik is an open source HTTP reverse proxy and load balancer. From 3.2.0 until 3.7.13, Traefik entrypoint defenses aliasHeadersStrategy, underscoreHeadersStrategy, and forwardedHeaders inspect req.Header but not req.Trailer, allowing an unauthenticated client to submit an aliasing or trusted...

CVE-2026-88004 Traefik entrypoint header-name sanitization bypassed via request trailers

Traefik is an open source HTTP reverse proxy and load balancer. From 3.2.0 until 3.7.13, Traefik entrypoint defenses aliasHeadersStrategy, underscoreHeadersStrategy, and forwardedHeaders inspect req.Header but not req.Trailer, allowing an unauthenticated client to submit an aliasing or trusted...

CVE-2026-88879

Traefik (HTTP reverse proxy and load balancer) is vulnerable to identity spoofing via dot-form header aliasing in versions v1.x, v2.x–v2.11.55, and v3.0.0–v3.7.11. Because Go canonicalizes header names on dashes only, a client can send a dot-form alias (e.g., X.Authenticated.User) alongside the c...

CVE-2026-88879 Traefik before v2.11.56 Identity Spoofing via Header Alias

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, XAuthUser and X.Auth.User are treated as three distinct headers by Traefik, while backends that derive variable...

CVE-2026-88879 Traefik before v2.11.56 Identity Spoofing via Header Alias

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, XAuthUser and X.Auth.User are treated as three distinct headers by Traefik, while backends that derive variable...

CVE-2026-88877 Traefik v3.7.0 Authentication Bypass via from-to-www-redirect

Traefik is a HTTP reverse proxy and load balancer. In versions = v3.7.0 and = v3.7.11, the Kubernetes ingress-nginx provider mishandles Ingresses that carry both an authentication annotation and the nginx.ingress.kubernetes.io/from-to-www-redirect annotation. For such Ingresses the provider creat...

PT-2026-89459

Name of the Vulnerable Software and Affected Versions Traefik versions 2.11.26 through 2.11.56 Traefik versions 3.4.2 through 3.7.12 Description Traefik contains a request smuggling issue related to the handling of the HTTP/1.1 Upgrade mechanism. The software forwards client-supplied Connection...

PT-2026-89472

Name of the Vulnerable Software and Affected Versions Traefik versions 1.x Traefik versions prior to 2.11.56 Traefik versions 3.0.0 through 3.7.11 Description Traefik fails to properly handle request headers that act as aliases for other header names. While Go treats headers like...