Why Visibility Alone Can’t Ensure the Security of Operational Technology Systems

The Importance of Defense-In-Depth Protection for Operational Technology Networks

Introduction

Operational Technology (OT) networks and Industrial Control Systems (ICS) are facing an increasing number of cyber threats and attacks. While gaining visibility into these networks is indeed a necessary first step, it is not sufficient to protect against intruders, malware, and system downtime. This article emphasizes the need for a defense-in-depth approach that combines visibility with proactive protection to effectively safeguard OT environments.

The Growing Threat Landscape

Over the past decade, the number of cyberattacks on critical infrastructure has surged dramatically. In 2021 alone, there were more attacks than in the previous ten years combined, and this number doubled again in 2022. These attacks are becoming increasingly sophisticated and brazen, with examples including state-sponsored actors hijacking delivery vehicles and infecting their OT cargo. Such incidents underscore the need for specialized OT-native defense strategies that go beyond traditional IT solutions.

Challenges in OT Environments

OT environments present unique challenges due to the delicate nature of the systems involved. These environments often feature a mix of new and legacy technology, with applications ranging from oil and gas production to power generation and manufacturing. Unlike IT environments that prioritize privacy, OT-native solutions focus on ensuring the continuity and availability of operations within these specialized settings. Therefore, the defense strategies devised for OT networks must be tailored specifically to their needs.

A Defense-in-Depth Approach

Traditional IT security approaches, including cloud security, tend to view cybersecurity as a software problem seeking a software solution. However, the physical world of automated factories and infrastructure operations demands a multi-pronged defense that goes beyond visibility alone. Employing a defense-in-depth strategy entails detecting and blocking threats before they occur and responding effectively if they do. Here are some practical steps organizations can take:

Trust Nothing, Scan Everything

One way to enhance visibility is by scanning all assets before connecting them to the network. This includes storage devices, vendor laptops, refurbished assets, and even brand-new assets from the factory. By implementing a policy that mandates physical scanning and providing portable scanning devices in vulnerable locations, organizations can ensure compliance with their security inspection protocols. Additionally, scanning tools that collect and centralize asset information during inspections significantly contribute to both visibility and protection strategies.

Protect the Endpoints

Deploying a software solution capable of detecting unexpected system changes and preventing them before they impact operations is crucial. For Windows-based systems or organizations seeking to use agent-based antivirus technology, it is essential to choose a solution specifically designed for OT environments. A true OT solution will possess a deep understanding of thousands of combinations of OT applications and protocols, providing aggressive and proactive protection against potential threats.

Secure Assets in Production

Availability is a top priority in OT security. Therefore, a proactive OT-native solution is recommended to maintain the continuity of known and trusted operations. Virtual patching, trust lists, and OT segmentation are effective measures to prevent and isolate potential intrusions or malicious traffic from spreading across the network. Physical appliances designed for OT environments can sit on the network, monitoring and blocking malicious activity without directly accessing the devices being protected.

Editorial and Advice

Operational Technology networks are increasingly becoming the primary target for cyber attacks due to their vulnerability and rich target opportunities. To mitigate these risks, organizations must adopt an OT-native defense-in-depth approach that prioritizes proactive prevention. Traditional IT security solutions fall short in protecting OT environments, where the focus should be on maintaining operational continuity. By implementing specialized solutions and adopting the recommended defense strategies, organizations can better safeguard their assets and environments.

The Role of Visibility

While visibility alone might not be sufficient to protect against cyber threats, it remains a critical component of a comprehensive defense-in-depth strategy. The ability to monitor and detect malicious activity within OT networks allows organizations to respond swiftly and effectively. However, visibility should not be the sole focus; rather, it should be complemented by proactive protection measures that go beyond simply identifying threats after they occur.

The Need for OT-Native Solutions

OT environments are unique and require specialized solutions that understand and can navigate the specific challenges posed by diverse protocols and applications. Organizations should prioritize selecting OT-native solutions that have a deep knowledge of the intricacies of OT systems, enabling them to provide effective protection tailored to the unique requirements of these environments.

The Importance of Continuity

For organizations that rely on OT networks, operational continuity is paramount. A breach or downtime in these networks can have severe consequences, including financial losses and potential safety hazards. By adopting a defense-in-depth approach that proactively prevents attacks, organizations can maintain continuity and minimize the risk of disruptions to their operations.

Ongoing Vigilance and Adaptation

The threat landscape is constantly evolving, requiring organizations to remain vigilant and continuously update their defense strategies. Attackers are always seeking new vulnerabilities and techniques, so organizations must stay up to date with the latest security measures to effectively protect their OT networks.

In conclusion, while visibility is an essential element of securing OT networks, organizations must go beyond mere visibility to implement proactive defense strategies. The increasing frequency and sophistication of cyberattacks on OT environments necessitate a defense-in-depth approach that combines visibility with specialized solutions and proactive protection measures. By adopting such an approach, organizations can minimize their vulnerability and maintain the continuity of their operations amidst the growing cyber threats.