{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "6.19.4"
              },
              {
                "fixed": "6.21.1"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "59399d8850befd5095ae1149e31f375cac9f0514"
            },
            {
              "fixed": "1d36c589d39f979327106bbcfb4cece7abaea502"
            }
          ],
          "repo": "https://github.com/tryghost/ghost",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-944x-pm95-3jpr"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-434"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53948.json"
  },
  "details": "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.",
  "id": "CVE-2026-53948",
  "modified": "2026-07-08T05:39:30.675901810Z",
  "published": "2026-06-24T18:06:30.077Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53948.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/TryGhost/Ghost/security/advisories/GHSA-944x-pm95-3jpr"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-53948"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Ghost: File Upload Content-Type Spoofing"
}