CVE-2026-53593

{
  "id": "CVE-2026-53593",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-20T20:16:44.883",
  "lastModified": "2026-10-24T20:10:00.137",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. Prior to version 1.8.224, the denylist that neutralizes dangerous file uploads (`Helper::$restricted_extensions`) is incomplete: it does not cover the `.pht` extension. The authenticated upload endpoint `POST /uploads/upload` (`SecureController@upload`) stores files with their original extension into the web-accessible directory `storage/app/public/uploads/` (served at `/storage/uploads/`). On the standard Apache + `libapache2-mod-php` deployment, the default handler `<FilesMatch \".+\\.ph(ar|p[3457]?|t|tml)$\">` executes `.pht`, so **any authenticated agent can upload a `.pht` web shell and run arbitrary commands as the web-server user** (`www-data`). This is a direct bypass of the fix for CVE-2025-48471, which added `phtml`/`phar` but not `pht` (nor `phtm`, `phps`). Version 1.8.224 contains an updated fix."
    },
    {
      "lang": "es",
      "value": "FreeScout es una mesa de ayuda y bandeja de entrada compartida gratuita construida con el framework Laravel de PHP. Antes de la versión 1.8.224, la lista de denegación que neutraliza las cargas de archivos peligrosos (’Helper::$restricted_extensions’) está incompleta: no cubre la extensión ’.pht’. El endpoint de carga autenticado ’POST /uploads/upload’ (’SecureController@upload’) almacena archivos con su extensión original en el directorio accesible por la web ’storage/app/public/uploads/’ (servido en ’/storage/uploads/’). En la implementación estándar de Apache + ’libapache2-mod-php’, el gestor predeterminado “<FilesMatch “.+\\.ph(ar|p[3457]?|t|tml)$”>” ejecuta ’.pht’, por lo que cualquier agente autenticado puede cargar un web shell ’.pht’ y ejecutar comandos arbitrarios como el usuario del servidor web (’www-data’). Esto es un bypass directo de la corrección para CVE-2025-48471, que añadió ’phtml’/’phar’ pero no ’pht’ (ni ’phtm’, ’phps’). La versión 1.8.224 contiene una corrección actualizada."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "freescout-help-desk",
          "product": "freescout",
          "versions": [
            {
              "version": "< 1.8.224",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 8.8,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-21T13:21:02.831385Z",
          "id": "CVE-2026-53593",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-434"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-27vp-fpg8-j8wv",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/freescout-help-desk/freescout/security/advisories/GHSA-27vp-fpg8-j8wv",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}