Sandbox Bypass in Heym Agent Tool Execution

CVE-2026-55376

What is CVE-2026-55376?

Heym's agentic systems allow authenticated users to create or edit workflows using a custom Python tool. However, prior to version 0.0.40, a vulnerability was identified where users could bypass the blacklist-based sandboxing mechanism. This occurred due to the inclusion of allowed standard-library modules that inadvertently exposed operating-system, process, and filesystem functionalities. The execution of potentially harmful commands, made possible through the use of the exec() function, enabled unauthorized control of the backend application user context. This issue has been addressed in version 0.0.40.

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