Major PLC Cyber Security Threats and Precautions to be taken to protect PLCs from cyber security attacks


Programmable logic controller (PLC) is a type of industrial control system that monitors and controls various types of equipment and processes in an industrial or commercial environment. Like any other computer system, PLCs can be vulnerable to cyber attacks that could compromise their operation or the safety and reliability of the systems they control.

There are several ways that a PLC can be targeted by a cyber attack, including:

  1. Network-based attacks: A PLC that is connected to a network can be targeted by an attacker who is able to gain access to the network. This could involve exploiting vulnerabilities in the network infrastructure or in the PLC itself.
  2. Physical attacks: An attacker with physical access to a PLC could potentially compromise it by connecting to it directly or installing malicious software onto it.
  3. Malicious software: PLCs can be infected with malware through various means, such as downloading infected software updates or opening infected emails.

To protect against these types of attacks, it is important to implement strong security measures, such as firewalls, encryption, and regular software updates. It is also important to limit physical access to PLCs and to follow good security practices, such as not using easily guessable passwords or sharing login credentials.

Major Cyber attacks targeting PLCs

There have been several reported cases of cyber attacks targeting programmable logic controllers (PLCs) in recent years. Some examples include:

  1. In 2020, researchers discovered that the malware known as “Triton” had been used to target a PLC at a petrochemical plant in the Middle East, causing a shutdown of the plant’s safety systems. Triton is a type of malware specifically designed to attack industrial control systems (ICS).
  2. In 2017, the malware known as “CrashOverride” or “Industroyer” was used to disrupt the power grid in Ukraine, causing widespread power outages. CrashOverride is capable of attacking PLCs used in power grids and other critical infrastructure.
  3. In 2016, the malware known as “Stuxnet” was discovered to have been used to target PLCs at an Iranian nuclear facility, causing the centrifuges used to enrich uranium to spin out of control and ultimately malfunction. Stuxnet is a highly sophisticated malware that is believed to have been developed by a state actor.

These are just a few examples of the types of cyber threats that have targeted PLCs in the past. It is important for organizations that rely on PLCs to be aware of these types of threats and to implement strong security measures to protect against them.

Precautions to Protect PLCs from Cyber Security Threats

There are several precautions that can be taken to protect programmable logic controllers (PLCs) from cyber attacks:

  1. Network security: PLCs that are connected to a network should be protected by a firewall to prevent unauthorized access. It is also important to use strong passwords and to regularly update them to prevent them from being guessed or cracked. Additionally, the use of encryption can help to protect data transmitted over the network.
  2. Physical security: Limiting physical access to PLCs can help to prevent attackers from physically connecting to or tampering with the devices. This may involve implementing security measures such as access control systems or security cameras.
  3. Software updates: PLCs should be regularly updated with the latest software to ensure that any vulnerabilities are patched. It is also important to verify the authenticity of software updates before installing them, as attackers may attempt to deliver malicious software under the guise of a legitimate update.
  4. Security awareness training: Ensuring that employees are aware of the importance of PLC security and the potential consequences of cyber attacks can help to prevent accidental or intentional security breaches. Training should include best practices for password management, avoiding phishing attacks, and identifying and reporting suspicious activity.
  5. Cybersecurity assessment: Regularly assessing the security of PLCs and the systems they control can help to identify and address any vulnerabilities before they are exploited by attackers. This may involve conducting penetration testing or using specialized software to scan for vulnerabilities.
  6. Segmentation: Segmenting the network that the PLCs are connected to can help to limit the scope of a potential attack and prevent an attacker from moving laterally within the network.
  7. Isolation: PLCs that control critical systems or processes may be isolated from other networks to reduce the risk of compromise. This may involve the use of dedicated networks or physically separating the PLCs from other systems.
  8. Security monitoring: Implementing security monitoring tools can help to detect suspicious activity on PLCs and the systems they control. This may include the use of network intrusion detection systems, log analysis tools, or real-time monitoring of system activity.
  9. Incident response plan: Having a plan in place to respond to a cyber attack can help to minimize the impact of an attack and ensure that systems are restored quickly. The plan should include procedures for identifying and containing the attack, recovering systems, and communicating with stakeholders.

Overall, it is important for organizations that rely on PLCs to be proactive in implementing strong security measures and regularly assessing and updating their security posture. By taking these precautions, organizations can protect their PLCs and the systems they control from cyber attacks and ensure the reliability and safety of their operations.