CVE-2026-111057

Mercury is a Python framework for sharing Jupyter notebooks as web applications and dashboards. From 3.0.0 until 3.2.4, a missing comma in BLOCKED_PATTERNS concatenates the /lab and /api/terminals regular-expression literals. Requests to /api/terminals therefore bypass the anonymous endpoint blocklist and reach Jupyter Server's terminal API. An unauthenticated attacker can use the resulting interactive operating-system shell to execute commands and access data available to the Mercury process.

An unauthenticated attacker can execute arbitrary system commands and access data available to the Mercury process. This leads to full server compromise.

Update Mercury to version 3.2.4 or later. Until patched, restrict access to the /api/terminals endpoint and do not expose instances on untrusted networks.