By Andre Froneman
In industrial cybersecurity, identifying attack vectors is crucial for building strong defense strategies. Human-Machine Interfaces [HMIs] are essential for operational oversight, but their web-based nature makes them attractive targets for cyberattacks. Hackers use IT-based reconnaissance and exploitation tactics to compromise web-based HMIs, potentially gaining access to an organization’s operational technology [OT] environment.
How Attacks Happen
Cybercriminals often begin by scanning for exposed web-based HMIs, exploiting leaked virtual private network [VPN] credentials, and identifying open ports with network scanning tools. Once inside, they may use any of the 154 known virtual network computing [VNC] exploits to extract passwords, move laterally across systems, or deploy ransomware. Advanced attackers target unmonitored areas such as building management systems, CCTV, access control, and industrial IoT [IIoT] networks to remain undetected.
Unauthorized access to SCADA and ICS systems can have severe consequences, including system disruptions, industrial process manipulation, and physical damage.
Strengthening HMI Security
A proactive cybersecurity approach can protect HMIs and OT systems. Key measures include:
Comprehensive Security Assessments. Beyond IT-to-OT testing, all OT components including IIoT, CCTV, access control, PLC code, and building management systems must be regularly assessed for vulnerabilities.
Network Segmentation. Implement segmentation following IEC 62443 or other cybersecurity frameworks to limit access and reduce attack surfaces.
Regular System Updates. Ensure OT endpoint detection, intrusion prevention, and intrusion detection systems are verified and updated. OT-native Zero Trust solutions can enhance security while respecting operational constraints.
Incident Response Planning. Develop plans for restoring HMIs, PLC code, historian databases, and engineering workstations in case of cyber incidents.
Cybersecurity Awareness Training. Employees, partners, and OEMs must be trained on best practices to serve as the first line of defense.
Pre-Production HMI Testing. Offline security scanning and vulnerability management solutions should be used in pre-production staging. Third-party security certifications can confirm HMIs are free from malware and supply chain risks.
OT Endpoint Protection. Deploy purpose-built OT security solutions with real-time threat detection, asset discovery, vulnerability assessment, file integrity monitoring, and centralized security enforcement. These solutions should include OT-specific malware protection that does not rely on signature updates.
Building a Resilient Cybersecurity Framework
As industrial systems grow, so do cybersecurity threats. A layered security approach including strong network controls, continuous testing, and employee awareness ensures industrial environments remain protected. By implementing these strategies, organizations can build a resilient infrastructure capable of withstanding evolving cyber risks.
