Defense strategies for evolving cyber-threats to industrial network security

Cybersecurity in industrial automation systems is still often overlooked, even though the cyber-threat landscape for operations technologies (OT) grows increasingly dangerous. Rising geopolitical tensions and greed spur attackers to target industrial environments. Given the severe risks, from financial loss to physical-safety hazards, developing a robust cybersecurity plan is critical for users and manufacturing facilities.

Industrial organizations, particularly in manufacturing, are prime targets for cyber-criminals. The manufacturing sector has consistently been the most targeted, accounting for more than 70% of all industrial ransomware attacks. These attacks are often financially motivated, with nearly a quarter of industrial companies reporting more than $5 million in damages per incident.

Threat terrain aided by IT-OT convergence

The primary cyber-threats to industrial networks still include:

• Ransomware continues to be the most prevalent cyber-threat. Attackers encrypt data and systems, demand large ransoms, and cause operational downtime and lost revenue.
• Nation-state attacks due to geopolitical conflicts increasingly extend into the cyber-realm, with advanced-threat groups targeting critical infrastructures.
• Insider threats are less frequent than external attacks, but whether they’re malicious or due to negligence, they can cause significant damage. A study from DTEX Systems found that 83% of organizations faced at least one insider security breach in the past year, with most attributed to negligence.
• Hacktivist groups typically cause minimal impact with distributed denial-of-service (DDoS) attacks, but some groups have demonstrated the ability to disrupt OT systems.

While not a direct cyber-threat, the digital transformation of industrial processes, known as Industry 4.0, is enabling vulnerabilities by blurring the lines between information technology (IT) and OT networks. Their convergence allows more efficient operations, but also expands potential cyber-attack surfaces. Traditional IT security measures, such as basic firewalls and antivirus software, are often insufficient to protect OT systems, which have unique requirements for reliability and real-time performance. The future of industrial cybersecurity relies on a unified approach that secures both environments.

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Future defense strategies

To counter the growing threats, a multi-layered, defense-in-depth approach is essential. Its key strategies include:

• Enhanced OT visibility. Gaining a comprehensive view of all OT assets, including legacy systems, is the first step to securing them. Continuous vulnerability assessments and threat intelligence are critical for identifying and addressing weak points.
• Network segmentation. Dividing larger networks into smaller, isolated zones of trust is an effective way to contain a breach, and prevent it from spreading. This helps protect critical systems from attacks that may originate in less-secure parts of the overall network.
• Zero-trust architecture. Instead of assuming all internal users and devices are safe, a zero-trust model requires strict verification for every access request, regardless of its origin. This is crucial for securing remote access functions and users, and preventing unauthorized system modifications.
• Artificial intelligence (AI) and machine learning (ML) are predicted to have a significant impact on future industrial cybersecurity. They can help monitor network traffic in real-time to detect anomalous activity, and provide earlier warnings of potential threats.
• Cyber deception. This strategic defense method involves using decoy systems to mislead and trap attackers, gain intelligence about their methods, and prevent them from reaching critical assets.

Despite the gains these cybersecurity strategies enable, manufacturers still face several crucial challenges as they strive to implement sufficient protections.

First, IT and OT security historically operated in isolation, but the convergence of their networks necessitates a cohesive security strategy. The future will require IT and OT security practices to align, achieve global visibility across both environments, and unify security policies to close gaps in defenses.

Second, many industrial environments rely on legacy equipment that wasn’t designed with modern cybersecurity in mind. New approaches, such as industrial firewalls with newer features, such as intrusion detection/prevention systems (IDS/IPS) and deep packet inspection (DPI), can protect existing assets without affecting network uptime.

Third, ongoing surges in ransomware and other criminal attacks on industrial targets underscore the need for proactive security measures. Companies must implement robust defenses like network segmentation and multi-factor authentication, and also have well-rehearsed incident response plans to minimize downtime and financial losses.