CVE-2025-66490

Описание

Traefik is an HTTP reverse proxy and load balancer. For versions prior to 2.11.32 and 2.11.31 through 3.6.2, requests using PathPrefix, Path or PathRegex matchers can bypass path normalization. When Traefik uses path-based routing, requests containing URL-encoded restricted characters (/, , Null, ;, ?, #) can bypass the middleware chain and reach unintended backends. For example, a request to http://mydomain.example.com/admin%2F could reach service-a without triggering my-security-middleware, bypassing security controls for the /admin/ path. This issue is fixed in versions 2.11.32 and 3.6.3.

A path normalization bypass has been discovered in Traefik. When Traefik is configured to route the requests to a backend using a matcher based on the path; if the request path contains an encoded restricted character from the following set ('/', '', 'Null', ';', '?', '#'), it’s possible to target a backend, exposed using another router, by-passing the middlewares chain.