What is GHSA-9754-6rhw-gj3h?

GHSA-9754-6rhw-gj3h is a security advisory published by GitHub Security Advisories with Medium severity. A vulnerability in jupyter/nbconvert versions \u003c= 7.17.0 allows for Cross-site Scripting (XSS) via...

Which CVE IDs does GHSA-9754-6rhw-gj3h cover?

GHSA-9754-6rhw-gj3h covers the following CVE IDs: CVE-2026-6658. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of GHSA-9754-6rhw-gj3h?

GHSA-9754-6rhw-gj3h has a CVSS v3 base score of 5.4, published by GitHub Security Advisories.

GHSA-9754-6rhw-gj3hMediumCVSS 5.4

A vulnerability in jupyter/nbconvert versions <= 7.17.0 allows for Cross-site Scripting (XSS) via...

Vendor

GitHub Security Advisories

Published

June 26, 2026

Last Modified

June 26, 2026

🔗 CVE IDs covered (1)

CVE-2026-6658 →

📋 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.

🔗 References (3)

https://nvd.nist.gov/vuln/detail/CVE-2026-6658
https://huntr.com/bounties/47570290-3b26-4477-8cfa-fdef7db5aefe
https://github.com/advisories/GHSA-9754-6rhw-gj3h