CVE-2026-40876

{
  "id": "CVE-2026-40876",
  "sourceIdentifier": "[email protected]",
  "published": "2026-04-21T20:17:01.263",
  "lastModified": "2026-10-26T22:10:00.163",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "goshs is a SimpleHTTPServer written in Go. Prior to 2.0.0-beta.6, goshs contains an SFTP root escape caused by prefix-based path validation. An authenticated SFTP user can read from and write to filesystem paths outside the configured SFTP root, which breaks the intended jail boundary and can expose or modify unrelated server files. The SFTP subsystem routes requests through sftpserver/sftpserver.go into DefaultHandler.GetHandler() in sftpserver/handler.go, which forwards file operations into readFile, writeFile, listFile, and cmdFile. All of those sinks rely on sanitizePath() in sftpserver/helper.go. helper.go uses a raw string-prefix comparison, not a directory-boundary check. Because of that, if the configured root is /tmp/goshsroot, then a sibling path such as /tmp/goshsroot_evil/secret.txt incorrectly passes validation since it starts with the same byte prefix. This vulnerability is fixed in 2.0.0-beta.6."
    },
    {
      "lang": "es",
      "value": "goshs es un SimpleHTTPServer escrito en Go. Antes de 2.0.0-beta.6, goshs contiene un escape de raíz SFTP causado por la validación de ruta basada en prefijos. Un usuario SFTP autenticado puede leer y escribir en rutas del sistema de archivos fuera de la raíz SFTP configurada, lo que rompe el límite de jaula previsto y puede exponer o modificar archivos de servidor no relacionados. El subsistema SFTP enruta las solicitudes a través de sftpserver/sftpserver.go hacia DefaultHandler.GetHandler() en sftpserver/handler.go, que reenvía las operaciones de archivo a readFile, writeFile, listFile y cmdFile. Todos esos sumideros dependen de sanitizePath() en sftpserver/helper.go. helper.go utiliza una comparación de prefijo de cadena en bruto, no una verificación de límite de directorio. Debido a eso, si la raíz configurada es /tmp/goshsroot, entonces una ruta hermana como /tmp/goshsroot_evil/secret.txt pasa incorrectamente la validación ya que comienza con el mismo prefijo de bytes. Esta vulnerabilidad está corregida en 2.0.0-beta.6."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "patrickhener",
          "product": "goshs",
          "versions": [
            {
              "version": "< 2.0.0-beta.6",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
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        "source": "[email protected]",
        "type": "Secondary",
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          "baseScore": 8.7,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "HIGH",
          "vulnAvailabilityImpact": "HIGH",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
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          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
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          "id": "CVE-2026-40876",
          "options": [
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              "exploitation": "poc"
            },
            {
              "automatable": "no"
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              "technicalImpact": "total"
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  "weaknesses": [
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      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-22"
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  "references": [
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      "url": "https://github.com/patrickhener/goshs/security/advisories/GHSA-5h6h-7rc9-3824",
      "source": "[email protected]",
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}