{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "0.14.3"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3ba8aca90e17e5410b7e8b227c9f29256ac3e875"
            }
          ],
          "repo": "https://github.com/gogs/gogs",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-3w28-36p9-w929"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-80"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52816.json"
  },
  "details": "Gogs is an open source self-hosted Git service. Prior to 0.14.3, the Jupyter Notebook (ipynb) sanitizer endpoint at POST /-/api/sanitize_ipynb allows arbitrary data: URIs without proper restrictions, potentially leading to Cross-Site Scripting (XSS). The endpoint uses bluemonday.UGCPolicy() with p.AllowURLSchemes(\"data\") which permits all data URI schemes including data:text/html, enabling attackers to inject malicious HTML/JavaScript. Additionally, the endpoint has no authentication middleware, allowing any registered user to exploit this vulnerability. This vulnerability is fixed in 0.14.3.",
  "id": "CVE-2026-52816",
  "modified": "2026-08-04T11:31:09.752977991Z",
  "published": "2026-06-24T20:26:34.151Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/gogs/gogs/releases/tag/v0.14.3"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52816.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/gogs/gogs/security/advisories/GHSA-3w28-36p9-w929"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-52816"
    },
    {
      "type": "FIX",
      "url": "https://github.com/gogs/gogs/commit/dd1bd9837aa196b3ed3a8ee21e5727b5d7a986a3"
    },
    {
      "type": "FIX",
      "url": "https://github.com/gogs/gogs/pull/8326"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N/E:P",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Gogs: Unauthenticated Jupyter Notebook (ipynb) Sanitizer allows arbitrary data: URIs leading to XSS"
}