CVE-2026-86044

Summary

JupyterLab Desktop prior to 4.6.2-1 exposed the getServerInfo API to renderers without verifying the origin of the current page, allowing an attacker to exploit a MathJax link in an untrusted notebook to redirect the renderer while retaining access to the preload bridge, then retrieve server credentials and execute arbitrary code via the Jupyter REST API.

Exploitability

Exploitation requires user interaction (clicking a malicious link in a notebook) and relies on a specific chain involving outdated MathJax handling in versions before 4.4.8; users on 4.4.8+ are protected from the first step.

Blast radius

Successful exploitation grants full remote code execution as the victim user, enabling data theft, lateral movement, or persistence within the local Jupyter environment.

Detection

No reliable host or network indicator is derivable from the published description.

Prioritized remediation

Upgrade to JupyterLab Desktop version 4.6.2-1 or later.

Analysis generated locally by garnet-coder (no data left the box). AI-assisted — verify against primary sources before acting.