{"id":"CVE-2025-47952","aliases":["GHSA-vrch-868g-9jx5","GO-2025-3719"],"url":"https://o3.security/vulnerability/CVE-2025-47952","summary":"Traefik allows path traversal using url encoding","details":"## Impact\n\nThere is a potential vulnerability in Traefik managing the requests using a `PathPrefix`, `Path` or `PathRegex` matcher.\n\nWhen 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.\n\n## Example\n\n```yaml\napiVersion: traefik.io/v1alpha1\nkind: IngressRoute\nmetadata:\n  name: my-service\nspec:\n  routes:\n    - match: PathPrefix(‘/service’)\n      kind: Rule\n      services:\n        - name: service-a\n          port: 8080\n      middlewares:\n        - name: my-middleware-a\n    - match: PathPrefix(‘/service/sub-path’)\n      kind: Rule\n      services:\n        - name: service-a\n          port: 8080\n```\n\nIn such a case, the request `http://mydomain.example.com/service/sub-path/%2e%2e/other-path` will reach the backend `my-service-a` without operating the middleware `my-middleware-a` unless the computed path is `http://mydomain.example.com/service/other-path` and should be computes by the first router (operating `my-middleware-a`).\n\n## Patches\n\n- https://github.com/traefik/traefik/releases/tag/v2.11.25\n- https://github.com/traefik/traefik/releases/tag/v3.4.1\n\n## For more information\n\nIf you have any questions or comments about this advisory, please [open an issue](https://github.com/traefik/traefik/issues).\n\n<details>\n<summary>Original Description</summary>\n### Summary\n\nPath traversal with \"/../\" using URL encodings (\"/%2e%2e\") allows for circumventing routing rules. \n\n### Details\n\nWhen having defined a route, you can path traverse using the URL encoded variant of /../ and reach endpoints that are not made publicly available. This issue has been found and fixed earlier with regular /../ and has been fixed in this CVE. This URL encoding trick works around that\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-32431\n\nSimply implementing a check on the URL encoding won't be sufficient as path traversal can take numerous formats. See examples here:\nhttps://book.hacktricks.wiki/en/pentesting-web/file-inclusion/index.html\n\n### PoC\n\nSetup a service with two endpoints: \"/public\" and \"/private\", which returns a 200 OK for both\nSetup a Traefik proxy with a single route which points to the service using path /public\n\nRegular requests to traefik /public will return 200 OK and to /private should return 404 (response by Traefik)\nWhen making a request to /public/%2e%2e/private you should receive a 200 OK.\n\n### Impact\nImpacts all traefik implementations with path prefix routes that expose only part of the downstream api\n\n### Suggestion\nProvide configuration property which disables all path traversals. Steps:\n1. Decode URL\n2. Evaluate and construct relative path (do traversal before route evaluation)\n3. Compare relative/evaluated path to configured routes (PathPrefix/pathRegexp)\n</details>","published":"2025-05-30T03:37:12.685Z","modified":"2026-08-12T03:51:37.650051383Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/traefik/traefik/v3","fixedVersion":"3.4.1"},{"ecosystem":"Go","name":"github.com/traefik/traefik/v2","fixedVersion":"2.11.25"},{"ecosystem":"Go","name":"github.com/traefik/traefik","fixedVersion":null}],"fix":{"url":"https://github.com/traefik/traefik/commit/08d5dfee0164aa54dd44a467870042e18e8d3f00","label":"traefik/traefik@08d5dfe"},"references":[{"type":"WEB","url":"https://github.com/traefik/traefik/releases/tag/v2.11.25"},{"type":"WEB","url":"https://github.com/traefik/traefik/releases/tag/v3.4.1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/47xxx/CVE-2025-47952.json"},{"type":"ADVISORY","url":"https://github.com/traefik/traefik/security/advisories/GHSA-vrch-868g-9jx5"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-47952"},{"type":"FIX","url":"https://github.com/traefik/traefik/commit/08d5dfee0164aa54dd44a467870042e18e8d3f00"},{"type":"PACKAGE","url":"https://github.com/traefik/traefik"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:37.650051383Z"}}