Vulnerability details
CVE-2026-86044
JupyterLab Desktop: One-Click Jupyter Server Token Leak leading to Remote Code Execution
Official description
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.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 9.6Critical | 3.1 | CVEProject cvelistV5 (CNA) (GitHub_M) | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| jupyterlab | jupyterlab-desktop | < 4.6.2-1 | CVEProject cvelistV5 (CNA) |
References and advisories
3- https://github.com/jupyterlab/jupyterlab-desktop/security/advisories/GHSA-2mr8-962v-wc67 x_refsource_CONFIRM
- https://github.com/jupyterlab/jupyterlab-desktop/commit/7f8f64ae796efae77d106612c95f0edd6c5dc273 x_refsource_MISC
- https://github.com/jupyterlab/jupyterlab-desktop/releases/tag/v4.6.2-1 x_refsource_MISC
Details
- Published
- 2026-11-07
- Last updated
- 2026-11-07
- State
- Published
- Assigner (CNA)
- GitHub_M
- Kolun priority
- 21 · Low
Exploit prediction (EPSS)
Weaknesses (CWE)
- CWE-601URL Redirection to Untrusted Site ('Open Redirect')