Modbus is a communication protocol that is widely used in industrial control systems (ICS). Modbus does not have any built-in security features, such as authentication or encryption, which makes it vulnerable to various attacks. One of the most common and effective attack techniques against Modbus assets is to send unauthenticated commands to manipulate or disrupt the operation of the devices. Remote code execution, buffer overflow, and certificate spoofing are other attack techniques, but they have less likelihood of quick success against Modbus assets. Reference: https://www.sciencedirect.com/science/article/pii/S2405959517300045