Mercury Web Framework Remote Code Execution Vulnerability

Mercury, a Python framework for sharing Jupyter notebooks as web applications and dashboards, is affected by a remote code execution vulnerability before version 3.2.6.

In default tokenless deployments, anonymous clients can create Jupyter kernels and send execute_request messages containing arbitrary Python. The issue arises because:

• The endpoint blocklist does not cover /api/kernels.
• The websocket wrapper previously tracked idle activity without authorizing executable messages.

This issue is fixed in version 3.2.6.