CVE-2026-53948

{
  "id": "CVE-2026-53948",
  "sourceIdentifier": "[email protected]",
  "published": "2026-06-24T19:17:12.460",
  "lastModified": "2026-10-25T22:10:00.150",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Ghost is a Node.js content management system. From 6.19.4 until 6.21.1, insufficient validation of the client-supplied Content-Type on Ghost's Admin API file upload endpoint allowed uploaded files to be served from the site with an attacker-chosen content type on S3/GCS storage backends. On installations that serve uploaded files from the same origin as the site, this could have been used to facilitate stored cross-site scripting against site visitors or staff. This vulnerability is fixed in 6.21.1."
    },
    {
      "lang": "es",
      "value": "Ghost es un sistema de gestión de contenido Node.js. Desde 6.19.4 hasta 6.21.1, la validación insuficiente del Content-Type proporcionado por el cliente en el endpoint de carga de archivos de la API de administración de Ghost permitió que los archivos cargados fueran servidos desde el sitio con un tipo de contenido elegido por el atacante en backends de almacenamiento S3/GCS. En instalaciones que sirven archivos cargados desde el mismo origen que el sitio, esto podría haberse utilizado para facilitar cross-site scripting almacenado contra los visitantes o el personal del sitio. Esta vulnerabilidad está corregida en 6.21.1."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "TryGhost",
          "product": "Ghost",
          "versions": [
            {
              "version": ">= 6.19.4, < 6.21.1",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N",
          "baseScore": 5.4,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "REQUIRED",
          "scope": "CHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 2.3,
        "impactScore": 2.7
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-06-25T13:17:17.045202Z",
          "id": "CVE-2026-53948",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-434"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/TryGhost/Ghost/security/advisories/GHSA-944x-pm95-3jpr",
      "source": "[email protected]"
    }
  ]
}