Why OT Security Can’t Be an Afterthought in Critical Infrastructure

In late 2023, the largest private water and wastewater utility in the U.S., American Water, announced a breach of its network. This led the company - which provides drinking water to 14 million Americans - to shut down some of its systems while investigating the breach.

Although the breach was contained in time, it highlighted the growing interdependence between OT and IT, and the risks that come with it.

This article explores why many companies neglect OT security and the best strategies to reverse this trend in 2025.

What is OT and OT Security?

Global security leader Fortinet, defines OT - operational technology as, “hardware and software systems used to monitor and control physical processes, devices, and infrastructure in industrial environments.”

These include Supervisory Control and Data Acquisition (SCADA) systems, Industrial Control Systems (ICS), and Programmable Logic Controllers (PLCs), all of which interact directly with physical operations to ensure safe, efficient functioning of critical infrastructure, e.g., transportation, manufacturing, power grids, and water treatment.

Think about what it takes to control robots on a manufacturing floor or monitor electrical grids in power plants: that is OT in play.

Having established the role OT plays, we’ll now explain OT security. It is the practice of safeguarding the OT systems that control industrial processes and equipment. Since OT is directly tied to physical operations, effective OT security also protects people.

By preventing unauthorized access to control systems, OT security helps prevent accidents such as chemical leaks, equipment malfunctions, blackouts or even explosions that could put workers and surrounding communities at risk.

The risks of insecure OT

While IT systems prioritize information safety and confidentiality, OT environments determine physical safety. However, insecure operational technology can have high-stakes consequences that no ransom can resolve.

Some risks of insecure OT include:

• Equipment malfunction: cyberattacks can cause equipment shutdowns or malfunctions, triggering a negative chain of events that threaten safety and operations.
• Environmental harm: Compromised OT can cause chemical leaks, uncontrolled emissions and oil spills—all detrimental to the environment.
• Service disruption: The disruption of critical infrastructure functions (e.g., utilities and transportation) could impact millions, causing chaos and discomfort.
• Threat to public safety: Insecure OT threatens public safety because compromised systems not only endanger operators but could also harm neighboring communities.
• Financial loss: Companies with compromised OT environments are at risk for regulatory penalties and lawsuits from affected parties.

Why OT is Frequently Overlooked in Cybersecurity Strategy

Operational technology systems have historically been independent of IT. OT was operated offline, physically, due to the belief that the absence of an external connection, and the presence of skilled workers was enough to safeguard the technology.

Moreover, OT hardware is mostly legacy systems. They were traditionally built for longevity, not security.

However, the emergence of Industry 4.0, also known as the Fourth Industrial Revolution, has created a digital manufacturing environment, where IT components are increasingly integrated into OT systems for “smarter production”.

The integration of OT systems with IT networks enables real-time data exchange, remote access, and increased connectivity through cloud computing.

While this integration indeed creates smarter and efficient industrial environments, it also makes the industrial sector a bigger target for threat actors. Each connected device is a potential entry point for attackers and extort critical infrastructure firms.

Data supports this: the global cost of cyberattacks is rising by 125% each year, with industrial companies losing up to $4.73 million per attack, according to a World Economic Forum analysis.

The convergence of IT-OT environments warrants a deeper look into access controls and endpoint security for OT systems, to keep attackers out and critical infrastructure safe.

Top 5 OT Security Tips for Protecting Industrial Environments

Securing operational technology is the key to keeping industrial environments and their people safe. However, safeguarding OT requires specialized security measures due to its legacy challenges and interdependence with physical components.

The following best practices, if adopted, can help protect critical infrastructure from modern cyber threats.

1. Segment your OT and IT networks

Isolating OT environments from the main business network reduces potential attack vectors. When OT systems and other networks operate independently of each other, a breach in the main network will not impact critical infrastructure.

Network segmentation strategies like demilitarized zones (DMZs) and firewalls help contain security breaches to one part of the network, preventing them from escalating into company-wide incidents that are much harder to control.

2. Harden OT systems through regular updates

Failure to update OT systems due to the need for continued operations creates security vulnerabilities which cybercriminals can exploit. This can be solved through regular patches and updates. Companies in highly regulated industries, however, may have to conduct thorough testing in simulated environments before applying patches.

3. Enforce strict access controls

Complement physical access restrictions to industrial machines by enforcing Multi-Factor Authentication (MFA) and Role-Based Access Control (RBAC). MFA verifies user identity while RBAC ensures they only have the privileges required for their tasks.

OT security teams must also review user permissions regularly and remove inactive accounts.

4. Continuous monitoring and threat detection

Like with other cybersecurity use cases, continuous monitoring allows organizations to detect suspicious activity in OT environments before they escalate. OT-specific intrusion detection and prevention systems (IDS/IPS) when deployed along with traditional SIEM tools, can detect unauthorized access attempts and unusual traffic in real-time.

5. Develop and test incident response plans

Incident response plans in OT environments must be tailored to the realities of industrial operations and tested to make sure they’re practical and effective. The plan should outline the roles of team members, communication protocols, and recovery strategies for various attack scenarios.

Adequate preparation using simulated cyberattacks helps organizations contain OT-targeted threats.

Key Takeaways

Effective security in industrial settings demands an ongoing collaboration between IT and OT teams. In fact, enterprises should consider building a dedicated OT security team that monitors the operational technology network.

Knowing that cyberattacks on infrastructure can translate into physical harm and utility shutdowns, OT security is no longer optional. It is essential for economic stability, national security and public welfare.

Organizations and government agencies must prioritize OT cyber-safety to protect people, economies, and the services that keep society running.