Skip to content
fr Sign in
5.4 Medium

CVE-2026-6658 A vulnerability in jupyter/nbconvert…

Description

A vulnerability in jupyter/nbconvert versions <= 7.17.0 allows for Cross-site Scripting (XSS) via unsanitized `text/vnd.mermaid` output in HTML exports. The `data_mermaid` block in `share/templates/lab/base.html.j2` renders `text/vnd.mermaid` cell output directly into HTML without escaping, enabling attackers to inject arbitrary HTML/JavaScript by breaking out of the `<pre>` tag. This vulnerability impacts any server using nbconvert to render notebooks as HTML, allowing attackers to execute arbitrary JavaScript in the context of users viewing the HTML export.

Affected products and versions

Product Affected versions Fixed in
jupyter/jupyter Versions not published

References

Timeline

  1. Published
  2. Last modified

Other CVEs of jupyter/jupyter

The 3 CVEs of jupyter/jupyter →
CVE-2026-6657 A vulnerability in jupyter-server versions 1.12.0 through 2.17.0 allows an attacker to bypass CORS origin validation… 6.1 Medium CVE-2026-5422 A path traversal vulnerability exists in jupyter-server version 2.17.0 due to an incorrect root directory boundary check… 6.8 Medium
Track this CVE