Modicon PLC IO Scan Status Disclosure
Medium Nessus Network Monitor Plugin ID 3856
SynopsisThe remote host may give an attacker information useful for future attacks.
DescriptionThe Modicon Quantum, Premium and Momentum brands of PLCs have a private SNMP MIB that is available on the Internet. The scan status may be obtained via an SNMP Get Request. The scan status is either idle, operational or stopped. An attacker may use this information to determine the status of a PLC.
SolutionChange default community strings to a value not easily guessed and filter access to the SNMP port.