PraisonAI versions prior to 4.6.78 contain a vulnerability in the JobWorkflowExecutor._exec_inline_python() function that allows remote code execution. The vulnerability arises because the sandbox intended to safely execute inline Python expressions is broken: the 'os' module is allowed to be imported, and dangerous functions like os.system() can be called. This enables an attacker to execute arbitrary OS commands with the privileges of the user running the workflow, particularly in multi-tenant or CI environments where untrusted YAML workflows may be executed.