Operational Technology (OT) systems are the backbone of critical infrastructure, responsible for monitoring and controlling physical processes. Recent incidents such as the Colonial Pipeline ransomware attack in May 2021 and the Kudankulam Nuclear Power Plant attack in October 2019 have demonstrated the vulnerability of OT networks to cyber-attacks.
Traditional security approaches for OT networks such as air-gapping and perimeter-based defenses are no longer sufficient to safeguard these critical systems. The interconnected nature of OT networks means that a single vulnerability can have far-reaching consequences, potentially impacting multiple industries and sectors. The Colonial Pipeline ransomware attack, which forced the company to shut down its pipeline operations for several days, caused significant disruptions to fuel supplies and resulted in fuel shortages in several states. The Kudankulam Nuclear Power Plant attack targeted the administrative network of the plant, highlighting the potential risk to critical infrastructure. To address the challenges of securing OT networks, a converged security approach is
necessary. A converged security approach will require increased collaboration between OT IT security professionals. This approach involves security assessment for OT systems, vulnerability threat management for all connected resources, continuous and proactive threat hunting, and compliance with industry standards.

1.Security Assessment for OT Systems: This assessment should include an inventory of all devices, applications, and systems connected to the OT network, as well as an analysis of the potential impact of a security breach. A thorough security assessment helps organizations prioritize security investments and develop an effective security strategy.
2.Vulnerability & Threat Management: This includes implementing security patches, monitoring network traffic for suspicious behaviour, and scanning for vulnerabilities in connected devices. Vulnerability and threat management must be implemented across all connected resources, including IoT devices, industrial control systems, and third-party applications.
3. Segmentation and Access Control: This includes segmenting the OT network into smaller isolated networks to limit the impact of a security breach. This approach can be achieved by implementing network segmentation technologies such as virtual local area networks (VLANs), network address translation (NAT), and firewalls. On the other hand, controlling access to the OT network is essential to prevent unauthorized access and limit the impact of a security breach. Access control mechanisms include authentication, authorization, accounting (AAA), and implementing a strong password policy.
4. Continuous and Proactive Threat Hunting: This includes monitoring network traffic for anomalies, analyzing system logs for suspicious activity, and conducting regular security audits. Proactive threat hunting helps organizations identify and respond to threats before they result in a security breach.
5. Incident response and recovery: This includes detection, analysis, containment, eradication, and recovery. In the detection stage, the security team uses various security tools such as intrusion detection and prevention systems (IDPS) to identify potential threats. In the analysis stage, the team investigates the nature and extent of the attack and determines its impact on critical systems. In the containment stage, the team isolates the affected systems to prevent further damage to critical assets. In the eradication stage, the team removes the malicious code from the system and eliminates the root cause of the attack. Finally, in the recovery stage, the team restores the affected systems to their normal functioning state.
6. Compliance with Industry Standards: Standards such as NIST, ISA, and IEC guide best practices for securing OT networks. Compliance with these standards helps ensure that the OT systems are secure and that the organization is prepared to meet regulatory requirements. Organizations must regularly review and update their security policies and procedures to comply with industry standards and regulations.

The Future is CONVERGED
The convergence of IT and OT systems is inevitable, and with it, the need for a converged security approach. By redefining the security approach for OT networks, organizations can safeguard their critical infrastructure systems against cyber threats. However, this requires a shift in mindset from traditional security approaches to a converged security approach.
A converged security approach is essential for safeguarding OT networks in todays complex threat landscape. By using a combination of visibility, threat detection, response, prevention, and ongoing monitoring, security teams can effectively protect these critical systems from both cyber and physical threats. While this approach requires a significant investment in both technology and personnel, the cost of a security breach can be far greater, both in terms of financial loss and damage to reputation.
Looking ahead, the future of the converged security holds great potential. This approach can help reduce operational downtime, minimize financial losses, and protect the reputation of an organization. On the security front, the integration of advanced technologies such as Artificial Intelligence, Machine Learning, and Automation can enable faster and more accurate threat detection, real-time monitoring, and automated responses to security incidents. However, successful implementation of this approach requires careful planning, design, and integration.
How can Gramax Cybersec Help?
GRAMAX Cybersec provides comprehensive security solutions covering people, process, and technology triad, and complete risk management. Our expertise in performing holistic OT assessments enables them to determine security gaps in critical Cyber-Physical Systems (CPS). With 24/7/365 monitoring, vulnerability, and threat management for all connected resources and compliance with industry standards, security solutions empower organizations to evaluate security maturity and improve OT visibility. As a trusted partner in securing OT networks, our SOC team monitors, analyses, and responds to potential threats in real-time to ensure the safety and continuity of critical operations. Moreover, GRAMAX Cybersec leverages the domain expertise of the GMR group in managing security for critical infrastructures, further strengthening their ability to safeguard OT networks.