What happens when a cyber-attack doesn’t just compromise data, but disrupts real-world operations or critical infrastructure? This is the high-stakes reality of Operational Technology (OT). Unlike traditional IT environments where the primary focus may be data confidentiality, OT systems interact directly with physical processes and hardware. 

Let’s explore what makes OT environments unique, why traditional IT security controls often fall short, and how specialized penetration testing can help protect critical operations. 

What is Operational Technology? 

Operational Technology (OT) refers to systems that monitor, control, or directly affect physical hardware in the real world. These are environments where digital commands translate into physical actions — starting or stopping motors, opening valves, tripping breakers, or adjusting temperature and pressure. Because these actions affect real equipment and people, OT systems have historically been designed around safety, availability, and deterministic behavior — often lacking basic security protections. 

Where you’ll find OT 

Common OT systems make up a range of Industrial Control Systems: Programmable Logic Controllers (PLCs), Remote Terminal Units (RTUs), Distributed Control Systems (DCS), and Safety Instrumented Systems (SIS). OT shows up across manufacturing, energy, water and wastewater, oil and gas, transportation, building automation, and even healthcare facilities. 

The basics of OT penetration testing

OT penetration testing is the practice of assessing whether an attacker could manipulate physical processes, disrupt operations, or bypass safety controls that keep everything in check. Unlike traditional IT penetration testing, OT testing must account for the fact that aggressive scanning, exploitation, or system instability can cause real-world safety incidents or production outages. As a result, OT assessments prioritize safety and uptime, rely heavily on passive techniques, and focus more on understanding how systems can be misused and less on exploiting vulnerabilities. 

Many OT attacks do not depend on zero-day exploits. Instead, they exploit protocols and commands that the systems were designed to accept under normal operations in trusted environments. In these cases, malicious activity can look indistinguishable from legitimate control traffic, making detection particularly challenging.  

How OT pen testing works in practice 

A mature OT pen test examines how an adversary could: 

• Move from IT networks into OT environments 
• Abuse engineering software or operator access 
• Send valid commands with malicious intent 
• Alter hardware values to degrade operations 
• Interfere or ultimately disable safety systems 

The goal is not simply to find vulnerabilities, but to understand how real attackers could leverage normal system behavior to create physical, operational, or safety impacts. This is where experience and deep knowledge of OT environments become critical — because in OT, the most dangerous attacks often use the system exactly as it was designed to be used. 

The CMMC impact on OT 

As CMMC pushes defense contractors and suppliers to demonstrate stronger asset visibility, risk management, monitoring, and incident response, OT environments can no longer sit outside the scope of cybersecurity programs. Many organizations supporting the defense industrial base operate manufacturing lines, test equipment, building automation, or other control systems that directly or indirectly impact Controlled Unclassified Information (CUI). The problem is that these systems are often implicitly trusted, poorly segmented, and sparsely monitored — creating blind spots that conflict with CMMC expectations around access control, system security plans, and continuous monitoring. 

Final thoughts 

The challenge is that traditional IT security controls and testing methods do not translate cleanly into OT environments. While CMMC emphasizes demonstrable risk reduction, OT systems often cannot be patched, aggressively scanned, or equipped with standard endpoint tools.  

This is why OT penetration testing needs specific expertise — to validate trust boundaries, identify unsafe exposure paths, and assess how legitimate control functionality could be abused.