Question

Perform a small analysis of the MODBUS protocol and its status is reported according to the security.  Highlight possible security issues and describe an attack model over
the protocol. Note, that the protocol was not designed to be secure.

Answer 1

This is the system which is made by Modicon systems. In this system, the data is transferred over the serial lines.
There are two devices which are generally involved in this communication.

• Modbus master:
• Modbus slave:

This is the open protocol which means that anyone can use this protocol and build their products on top of it.

But there are vulnerabilities which are present in this system

• There is no confidentiality present in the system transferred messages as they are sent in the clear text thus the messages are too vulnerable.
• There is no authentication present in the protocol thus anyone in between can enter into the system and can hamper the system.
• The sessions which are created in this Modbus protocol are very short-lived thus an attacker can interfere and can create a new session which the user may not know that hacker is there on the other end.

Thus due to these reasons the  Modbus protocol being very simple can be dangerous.

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