Upstream information

CVE-2026-6658 at MITRE

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.

SUSE information

Overall state of this security issue: Does not affect SUSE products

This issue is currently rated as having moderate severity.

CVSS v3 Scores
CVSS detail CNA (Huntr.dev)
Base Score 5.4
Vector CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required Low
User Interaction Required
Scope Changed
Confidentiality Impact Low
Integrity Impact Low
Availability Impact None
CVSSv3 Version 3
SUSE Bugzilla entry: 1269365 [NEW]

No SUSE Security Announcements cross referenced.

SUSE Timeline for this CVE

CVE page created: Fri Jun 26 14:09:19 2026
CVE page last modified: Fri Jun 26 18:25:40 2026