MODBUS/TCP 'Force Listen Mode' Function Code Detection

Info Nessus Network Monitor Plugin ID 7101

Synopsis

The MODBUS/TCP client has sent a MODBUS server a Force Listen Mode request.

Description

The MODBUS/TCP client has sent a MODBUS server a Force Listen Mode request. The Force Listen Mode request, function code 8 (0x08) and subfunction code 4 (0x04), will cause the target server into listen-only mode; i.e., it will not send any responses. This function is typically implemented only in serial devices.

Solution

N/A

Plugin Details

Severity: Info

ID: 7101

Version: 1.0

Family: SCADA

Published: 2014/02/26

Modified: 2014/06/18

Risk Information

Risk Factor: Info