Gogs: Unauthenticated Jupyter Notebook (ipynb) Sanitizer allows arbitrary data: URIs leading to XSS_CVE-2026-52816

{
    "lastseen": "",
    "description": "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.",
    "published": "2026-06-24T20:26:34.151Z",
    "modified": "2026-06-24T20:26:34.151Z",
    "type": "cve",
    "title": "Gogs: Unauthenticated Jupyter Notebook (ipynb) Sanitizer allows arbitrary data: URIs leading to XSS",
    "source": "GitHub_M",
    "references": "https://github.com/gogs/gogs/security/advisories/GHSA-3w28-36p9-w929\nhttps://github.com/gogs/gogs/pull/8326\nhttps://github.com/gogs/gogs/commit/dd1bd9837aa196b3ed3a8ee21e5727b5d7a986a3\nhttps://github.com/gogs/gogs/releases/tag/v0.14.3",
    "id": "CVE-2026-52816",
    "bulletinFamily": "",
    "cwe": [
        "CWE-80"
    ],
    "cvelist": null,
    "sourceData": "gogs gogs < 0.14.3",
    "sourceHref": "",
    "cvss": {
        "score": 5.4,
        "severity": "MEDIUM",
        "vector": "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",
        "version": "4.0"
    },
    "cvss2": [],
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        "baseScore": 0,
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        "privilegesRequired": "",
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        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
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    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "gogs",
    "version": "< 0.14.3",
    "vendor": "gogs",
    "ai_description": "",
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    "ai_score": 0
}