CVE-2026-25766

{"id": "CVE-2026-25766", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.3, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 1.4, "exploitabilityScore": 3.9}]}, "published": "2026-02-19T16:27:15.497", "references": [{"url": "https://github.com/labstack/echo/commit/b1d443086ea27cf51345ec72a71e9b7e9d9ce5f1", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/labstack/echo/pull/2891", "tags": ["Issue Tracking", "Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/labstack/echo/security/advisories/GHSA-pgvm-wxw2-hrv9", "tags": ["Exploit", "Vendor Advisory"], "source": "security-advisories@github.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-22"}]}], "descriptions": [{"lang": "en", "value": "Echo is a Go web framework. In versions 5.0.0 through 5.0.2 on Windows, Echo\u2019s `middleware.Static` using the default filesystem allows path traversal via backslashes, enabling unauthenticated remote file read outside the static root. In `middleware/static.go`, the requested path is unescaped and normalized with `path.Clean` (URL semantics). `path.Clean` does not treat `\\` as a path separator, so `..\\` sequences remain in the cleaned path. The resulting path is then passed to `currentFS.Open(...)`. When the filesystem is left at the default (nil), Echo uses `defaultFS` which calls `os.Open` (`echo.go:792`). On Windows, `os.Open` treats `\\` as a path separator and resolves `..\\`, allowing traversal outside the static root. Version 5.0.3 fixes the issue."}, {"lang": "es", "value": "Echo es un marco web de Go. En las versiones 5.0.0 a 5.0.2 en Windows, el `middleware.Static` de Echo que utiliza el sistema de archivos predeterminado permite recorrer rutas mediante barras invertidas, lo que permite la lectura de archivos remotos no autenticados fuera de la ra\u00edz est\u00e1tica. En `middleware/static.go`, la ruta solicitada no se escapa y se normaliza con `path.Clean` (sem\u00e1ntica de URL). `path.Clean` no trata `\\` como un separador de ruta, por lo que las secuencias `..\\` permanecen en la ruta limpia. La ruta resultante se pasa entonces a `currentFS.Open(...)`. Cuando el sistema de archivos se deja en el valor predeterminado (nil), Echo utiliza `defaultFS`, que llama a `os.Open` (`echo.go:792`). En Windows, `os.Open` trata `\\` como un separador de ruta y resuelve `..\\`, lo que permite el recorrido fuera de la ra\u00edz est\u00e1tica. La versi\u00f3n 5.0.3 corrige el problema."}], "lastModified": "2026-02-23T20:17:51.353", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:labstack:echo:*:*:*:*:*:go:*:*", "vulnerable": true, "matchCriteriaId": "27FD7D9D-DB8A-4CC1-8024-72E6C1865D46", "versionEndExcluding": "5.0.3", "versionStartIncluding": "5.0.0"}], "operator": "OR"}, {"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*", "vulnerable": false, "matchCriteriaId": "A2572D17-1DE6-457B-99CC-64AFD54487EA"}], "operator": "OR"}], "operator": "AND"}], "sourceIdentifier": "security-advisories@github.com"}