CVE-2026-3431: Sim

Critical severity, CVSS 9.8. EPSS: 0.6% chance of exploitation in the next 30 days.

On SimStudio version below to 0.5.74, the MongoDB tool endpoints accept arbitrary connection parameters from the caller without authentication or host restrictions. An attacker can leverage these endpoints to connect to any reachable MongoDB instance and perform unauthorized operations including reading, modifying, and deleting data.

Affected products

• Sim Sim: before 0.5.74 (fixed in 0.5.74)

Published 2026-03-02. Last modified 2026-06-17.