ModScan is a new tool designed to map a SCADA MODBUS TCP based network. The tool is written in python for portability and can be used on virtually any system with few required libraries.
You can download it from the following link: https://packetstormsecurity.com/files/download/69254/modscan.py.txt
Source: https://packetstormsecurity.com/files/69254/modscan.py.txt.html