Traefik (pronounced traffic) is an HTTP reverse proxy and load balancer. Prior to versions 2.11.25 and 3.4.1, there is a potential vulnerability in Traefik managing the requests using a PathPrefix, Path or PathRegex matcher. When Traefik is configured to route the requests to a backend using a matcher based on the path, if the URL contains a URL encoded string in its path, it’s possible to target a backend, exposed using another router, by-passing the middlewares chain. This issue has been patched in versions 2.11.25 and 3.4.1.

AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CWE-22

https://github.com/traefik/traefik/commit/08d5dfee0164aa54dd44a467870042e18e8d3f00

https://github.com/traefik/traefik/releases/tag/v2.11.25

https://github.com/traefik/traefik/releases/tag/v3.4.1

https://github.com/traefik/traefik/security/advisories/GHSA-vrch-868g-9jx5