How to protect operational technology from targeted cyber attacks

Protecting operational technology (OT) from targeted cyber attacks is a paramount concern in a world full of pervasive connectivity and a complex geopolitical climate. The digital world, while giving way to unprecedented efficiencies across industries, has simultaneously exposed the vulnerabilities of OT systems, the backbone of critical infrastructure, from power grids and manufacturing plants to transportation networks and water treatment facilities.

Unlike IT systems, which primarily handle data and information, OT systems control the physical world. This distinction is crucial since a cyber attack on OT can have devastating real-world consequences, far surpassing the impact of a typical data breach. For example, a successful attack could cripple water treatment facilities causing shortages or contamination or even sabotage manufacturing processes, resulting in faulty products and potentially endangering users.

The hidden dangers of convergence

Historically, OT systems operated in relative isolation, often referred to as “air-gapped” networks, physically separated from the internet and corporate IT infrastructure. This perceived isolation offered a degree of inherent security.

However, the rise of the industrial internet of things (IIoT) and the growing need for real-time data analysis, remote monitoring and management have driven the convergence of IT and OT. This convergence, while unlocking significant operational advantages such as improved efficiency and predictive maintenance, has inadvertently expanded the attack surface, making OT systems vulnerable to a wider range of cyber threats that were previously considered improbable. The blurring of the lines between IT and OT has created new pathways for attackers to penetrate previously isolated systems.

Targeted cyber attacks against OT are becoming increasingly sophisticated and frequent. Attackers are no longer just seeking financial gain; their motivations can range from geopolitical agendas and industrial espionage to the sheer desire to cause disruption and chaos. Recent headlines have highlighted the increasing frequency of attacks on OT, a trend supported by data showing no signs of slowing. In fact, attacks targeting industrial automation protocols surged to 79 percent in 2024.  

For example, attackers might target programmable logic controllers (PLCs), the workhorses of industrial automation, to manipulate processes, cause equipment malfunction or even trigger safety shutdowns.

Critical infrastructure is under threat

The UK, like other industrialized nations, faces a growing threat landscape targeting its critical infrastructure. While specific details of attacks are often kept confidential for national security reasons, publicly available information and expert analysis paint a concerning picture.

The 2017 WannaCry ransomware attack, though not specifically aimed at OT, served as a stark reminder of the interconnectedness of modern systems and the potential for cascading effects. While the primary target was IT systems, the disruption to the National Health Service (NHS) demonstrated how a cyber attack can disrupt essential services and potentially impact even OT environments indirectly. Imagine a hospital’s IT systems are crippled, preventing doctors from accessing patient records or controlling critical medical equipment connected to OT systems.

Beyond ransomware, there have been reports and analyses of attempted intrusions into energy facilities, water treatment plants and other critical infrastructure. These incidents underscore the constant probing and vulnerability scanning that these systems face. For instance, a successful attack on a water treatment facility could allow attackers to manipulate chemical levels, potentially poisoning the water supply. The potential consequences of such attacks are severe, ranging from economic damage and disruption of essential services to environmental disasters and threats to public health and safety.

The ripple effect

Building a robust OT security posture requires a multi-layered approach. While complete air-gapping is no longer a realistic option, network segmentation remains crucial.

Dividing the OT network into smaller, isolated zones (micro-segmentation) can limit the lateral movement of attackers in the event of a breach. Think of it like compartmentalizing a ship; if one section is breached, the damage is contained. Intrusion detection and prevention systems (IDPS) that understand OT environments are essential for detecting and blocking malicious traffic. These systems must be carefully tuned to avoid disrupting the delicate balance of OT operations. Unlike IT systems where frequent patching is the norm, patching OT systems can be complex due to compatibility issues and rare maintenance windows. A risk-based approach is necessary, prioritizing critical systems and vulnerabilities.

Security hardening of OT devices and systems, including disabling unnecessary services, implementing strong authentication and limiting access to authorized personnel, is vital.

Cyber security awareness training for OT personnel is crucial, as human error can often be a contributing factor in successful attacks. OT staff need to understand the specific threats to their systems and follow security best practices. A well-defined incident response plan is essential for minimizing the impact of an attack. The plan should outline procedures for detection, containment, eradication, recovery and communication with stakeholders.

Compliance with legislation

Crucially, nurturing strong relationships with OT suppliers is paramount as they provide valuable insights into potential vulnerabilities and security best practices. Organizations should work closely with their suppliers to develop a shared understanding of security responsibilities and establish clear communication channels for reporting and addressing security incidents.

Regular security assessments and audits, conducted in conjunction with suppliers, can help identify and mitigate potential weaknesses or compliance with legislation. Building trust and fostering a collaborative approach with suppliers can significantly enhance an organization’s overall OT security posture. Finally, collaboration and information sharing within the industry and with government agencies are vital for staying ahead of the constantly evolving cyber threat landscape.

Continuous vigilance, sustained investment in security and close collaboration are essential for ensuring the safety and reliability of OT systems in the face of increasingly sophisticated cyber attacks.