A denial of service was found in the PowerFlex 525 variable frequency drive used in industrial systems to control the frequency of industrial motors. This finding allows an attacker to crash the Common Industrial Protocol (CIP) in a way that it does not accept any new connection. The current connections however, are kept active, giving attackers complete control over the device. There are no known public exploits that target this vulnerability.

https://applied-risk.com/application/files/4215/5385/2294/Advisory_AR2019004_Rockwell_Powerflex_525_Denial_of_Service.pdf