CVE-2026-52816
MEDIUMGogs < 0.14.3 - Unauthenticated Cross-Site Scripting via ipynb Sanitizer
Title source: manualDescription
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.
References (4)
Core 4
Core References
X_Refsource_Confirm x_refsource_confirm
https://github.com/gogs/gogs/security/advisories/GHSA-3w28-36p9-w929
X_Refsource_Misc x_refsource_misc
https://github.com/gogs/gogs/pull/8326
X_Refsource_Misc x_refsource_misc
https://github.com/gogs/gogs/commit/dd1bd9837aa196b3ed3a8ee21e5727b5d7a986a3
X_Refsource_Misc x_refsource_misc
https://github.com/gogs/gogs/releases/tag/v0.14.3
Scores
CVSS v4
5.4
EPSS
0.0068
EPSS Percentile
47.6%
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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
no
Technical Impact
partial
Details
CWE
CWE-80
Status
published
Products (1)
gogs/gogs
< 0.14.3
Published
Jun 24, 2026
Tracked Since
Jun 25, 2026