CVE-2026-52816

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/gogs/gogs/commit/dd1bd9837aa196b3ed3a8ee21e5727b5d7a986a3
https://github.com/gogs/gogs/pull/8326
https://github.com/gogs/gogs/releases/tag/v0.14.3
https://github.com/gogs/gogs/security/advisories/GHSA-3w28-36p9-w929
https://github.com/gogs/gogs/security/advisories/GHSA-3w28-36p9-w929

Configurations

No configuration.

History

25 Jun 2026, 21:16

Type	Values Removed	Values Added
References	~~() https://github.com/gogs/gogs/security/advisories/GHSA-3w28-36p9-w929 -~~	() https://github.com/gogs/gogs/security/advisories/GHSA-3w28-36p9-w929 -

24 Jun 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-24 21:16

Updated : 2026-06-25 21:16

NVD link : CVE-2026-52816

Mitre link : CVE-2026-52816

CVE.ORG link : CVE-2026-52816

JSON object : View

Products Affected

No product.

CWE

CWE-80

Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)

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