Zen Cart 1.5.7b allows admins to execute arbitrary OS commands by inspecting an HTML radio input element (within the modules edit page) and inserting a command.
https://github.com/MucahitSaratar/zencart_auth_rce_poc
http://packetstormsecurity.com/files/161613/Zen-Cart-1.5.7b-Remote-Code-Execution.html