{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "9.0.0-alpha.1"
              },
              {
                "fixed": "9.9.1-alpha.11"
              },
              {
                "introduced": "0"
              },
              {
                "fixed": "8.6.81"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "74f85e9b1682648a7bde106ab401adb4183132c6"
            },
            {
              "introduced": "0"
            },
            {
              "fixed": "ccf85f95b382a1efcea360f3ef3ba7f1bb3abde3"
            },
            {
              "fixed": "bccd92c768e7e793239f179718b804e7ce1ae125"
            },
            {
              "fixed": "97c6a78d19f976ec756c1295f08a8fccab90799a"
            },
            {
              "fixed": "be12a60d65b6e140481882037fb896b1f951df50"
            }
          ],
          "repo": "https://github.com/parse-community/parse-server",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-v8x7-r927-cc93"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-434"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55778.json"
  },
  "details": "Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.9.1-alpha.11 and 8.6.81, the default fileUpload.fileExtensions blocklist could be bypassed by uploading a file with a non-standard or compound extension and dangerous content type, allowing storage adapters such as S3 and GCS to serve attacker-supplied active content and enable stored cross-site scripting. This issue is fixed in versions 9.9.1-alpha.11 and 8.6.81.",
  "id": "CVE-2026-55778",
  "modified": "2026-08-12T03:51:30.085583904Z",
  "published": "2026-07-08T20:50:52.531Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/parse-community/parse-server/releases/tag/8.6.81"
    },
    {
      "type": "WEB",
      "url": "https://github.com/parse-community/parse-server/releases/tag/9.9.1-alpha.11"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55778.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/parse-community/parse-server/security/advisories/GHSA-v8x7-r927-cc93"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-55778"
    },
    {
      "type": "FIX",
      "url": "https://github.com/parse-community/parse-server/commit/97c6a78d19f976ec756c1295f08a8fccab90799a"
    },
    {
      "type": "FIX",
      "url": "https://github.com/parse-community/parse-server/commit/be12a60d65b6e140481882037fb896b1f951df50"
    },
    {
      "type": "FIX",
      "url": "https://github.com/parse-community/parse-server/pull/10505"
    },
    {
      "type": "FIX",
      "url": "https://github.com/parse-community/parse-server/pull/10506"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Parse Server: Stored XSS via non-standard file extension bypassing file upload extension blocklist"
}