AUGUST 24, 2026
Live Feed
Back to database
Case File

CVE-2026-6658

MEDIUM · CVSS 5.4 EPSS 0.13%

Source: NVD + CISA KEV + EPSS (historical backfill) · Published 2026-06-26 · Last synced 2026-08-04

CyberRota Analysis

This is a medium severity vulnerability with a CVSS score of 5.4. It affects Java.

CVE
CVE-2026-6658
Severity
MEDIUM
CVSS
5.4
EPSS
0.13%
Java

Original NVD 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.