---
id: CVE-2026-86044
title: >-
  JupyterLab Desktop: One-Click Jupyter Server Token Leak leading to Remote Code
  Execution
summary: >-
  JupyterLab Desktop is the cross-platform desktop application for JupyterLab.
  Prior to 4.6.2-1, JupyterLab Desktop exposed getServerInfo to the renderer
  without confirming that the current page still had the local Jupyter server
  origin. I…
severity: critical
cvss: 9.6
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H'
cvssSource: cna
cwe:
  - CWE-601
vendor: jupyterlab
product: jupyterlab-desktop
affected:
  - jupyterlab-desktop < 4.6.2-1
published: '2026-11-06'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T20:30:53.266Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-86044'
references:
  - url: >-
      https://github.com/jupyterlab/jupyterlab-desktop/security/advisories/GHSA-2mr8-962v-wc67
    label: >-
      https://github.com/jupyterlab/jupyterlab-desktop/security/advisories/GHSA-2mr8-962v-wc67
  - url: >-
      https://github.com/jupyterlab/jupyterlab-desktop/commit/7f8f64ae796efae77d106612c95f0edd6c5dc273
    label: >-
      https://github.com/jupyterlab/jupyterlab-desktop/commit/7f8f64ae796efae77d106612c95f0edd6c5dc273
  - url: 'https://github.com/jupyterlab/jupyterlab-desktop/releases/tag/v4.6.2-1'
    label: 'https://github.com/jupyterlab/jupyterlab-desktop/releases/tag/v4.6.2-1'
tags:
  - cve.org
ingestedAt: '2026-11-06T21:04:04.247Z'
epss: 0.00313
epssPercentile: 0.24314
---

## Overview

JupyterLab Desktop is the cross-platform desktop application for JupyterLab. Prior to 4.6.2-1, JupyterLab Desktop exposed getServerInfo to the renderer without confirming that the current page still had the local Jupyter server origin. In a local managed session using JupyterLab before 4.4.8, an attacker can place a crafted MathJax link in an untrusted notebook. If a victim opens the notebook and clicks the link, the existing renderer navigates to an attacker-controlled site while retaining access to the preload bridge. The site can call getServerInfo to obtain the local server URL and authentication token, then use the Jupyter REST API to create and trust a notebook that executes arbitrary code as the victim. Users whose environment already uses JupyterLab 4.4.8 or later are unaffected because the corrected link handling breaks the first step of the chain. This vulnerability is fixed in 4.6.2-1.

## Affected

- `jupyterlab-desktop < 4.6.2-1`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.