HI,
This question may seems naive but sometimes we have to look back to detect vulnerable points in the control system for virus threats!
Consider a control system which is connected to various package PLCs with individual Modbus links all using RS-485 physical layer and just transferring data by Modbus known commands.
Each PLC is connected to the control system by a dedicated Modbus module.
Question is: Can an infected PLC send virus via this Modbus link to the control system and infect it?
This question may seems naive but sometimes we have to look back to detect vulnerable points in the control system for virus threats!
Consider a control system which is connected to various package PLCs with individual Modbus links all using RS-485 physical layer and just transferring data by Modbus known commands.
Each PLC is connected to the control system by a dedicated Modbus module.
Question is: Can an infected PLC send virus via this Modbus link to the control system and infect it?