A CWE-290: Authentication Bypass by Spoofing vulnerability exists in all versions of the Modicon M580, Modicon M340, Modicon Quantum, and Modicon Premium which could cause an elevation of privilege by conducting a brute force attack on Modbus parameters sent to the controller.
https://www.talosintelligence.com/vulnerability_reports/TALOS-2018-0741
https://www.schneider-electric.com/en/download/document/SEVD-2019-134-11/