GitHub Advisoryadvisory · Go

GHSA-6vxv-wg6j-5qwp Gogs: XSS in .ipynb files renderer due to outdated notebookjs

HIGH Published 2026-06-19 Modified 2026-06-19 Official page ↗
Ecosystem
Go
Packages
gogs.io/gogs
Severity
High
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
Weaknesses
CWE-1395, CWE-80
Reviewed
2026-06-19

Affected packages

• Go gogs.io/gogs: < 0.14.3 → fixed in 0.14.3

Description

Summary Gogs renders Jupyter notebook files (`.ipynb`) using jsvine/notebookjs, but the version is outdated, missing patches for known XSS vulnerabilities. Details Gogs uses version 0.4.2 of notebookjs to render Jupyter notebook files: https://github.com/gogs/gogs/blob/7297aee50d4c115836c7de8a3a233daaef87b911/templates/base/head.tmpl#L47 The latest version of jsvine/notebookjs is 0.8.3, patching many XSS vulnerabilities in its releases. The proof of concept below shows an example working payload that renders HTML through Markdown. PoC 1. Create a new repository 2. Create a file inside the repository named `xss.ipynb` and give it the following content: ```json {"cells": [{"cell_type": "markdown", "metadata": {}, "source": [""]}], "metadata": {}, "nbformat": 4, "nbformat_minor": 2} ``` 3. Save the file and view the file in Gogs. Notice that the XSS popup triggers: Impact Any user with rights to create repositories can create XSS payloads that take over the victim's account when visited. Either through their own exploration of the files or by directly linking them the vulnerable URL.

Related

Weakness · CWE (2)

  • CWE-1395 Dependency on Vulnerable Third-Party Component weakness
  • CWE-80 Improper Neutralization of Script-Related HTML Tags in a Web Page weakness

References