{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "0"
                  },
                  {
                    "last_affected": "0.9.64"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StandardRange"
              }
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "ecf8c031d3c955508a0d3887acd61d970022db79"
            }
          ],
          "repo": "https://github.com/appflowy-io/appflowy-cloud",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-79"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/127xxx/CVE-2026-127203.json"
  },
  "details": "AppFlowy Cloud through 0.9.64 contains a stored cross-site scripting vulnerability that allows authenticated workspace members to upload blobs with unvalidated Content-Type values that are later served inline without a Content-Disposition header or authentication on the retrieval route. Attackers can upload a text/html or image/svg+xml blob via put_blob_handler, which is then rendered as an active same-origin document through the unauthenticated get_blob_handler endpoint and cached immutably for one year, enabling persistent script execution against any visitor who accesses the URL.",
  "id": "CVE-2026-127203",
  "modified": "2026-11-13T02:30:33.634862871Z",
  "published": "2026-11-12T16:42:40.069Z",
  "references": [
    {
      "type": "EVIDENCE",
      "url": "https://gist.github.com/mtholmquist/9b9683104fc3b5d78a488c06a6674e5c"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/AppFlowy-IO/AppFlowy-Cloud"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/127xxx/CVE-2026-127203.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-127203"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/appflowy-cloud-stored-xss-via-blob-upload-content-type"
    }
  ],
  "schema_version": "1.9.2",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "AppFlowy Cloud 0.9.64 Stored XSS via Blob Upload Content-Type"
}