A short introduction to ICS and OT security
Elementrica
For decades, safety in industry meant protecting people from machines. Now there is a second, quieter threat: a cyberattack that can halt production, wreck equipment, and in the worst case put lives at risk. The more industrial systems connect to IT and the internet, the larger the attack surface gets. This piece introduces ICS and OT security: the core terms, the real threats, and a few solid places to start.
Why ICS and OT carry a different kind of risk
In classic IT, confidentiality usually comes first, then integrity and availability. In the industrial world that order flips. Availability and integrity come first, because an attack reaches into the physical world: a production line running, power getting delivered, buildings staying heated.
Industrial equipment increasingly ships with web interfaces, databases, and cloud connections. That makes it easier to run, but it opens attack paths that simply did not exist on isolated installations.
What ICS means
Industrial Control Systems (ICS) are the hardware and software that monitor and control industrial processes. You will find them in manufacturing, power, water treatment, and transport.
ICS includes SCADA systems (supervisory control and data acquisition) and PLCs (programmable logic controllers), among others. These run the automation and the real-time control.
What OT means
Operational Technology (OT) is the systems and devices that interact with the physical world, either reading its state or changing it. OT is a broader term than ICS and contains it.
Beyond control systems, OT also covers building management, fire safety installations, and physical access control. Anything that drives the physical world.
What can actually go wrong
NIST 800-82 (Guide to Operational Technology Security) collects the incidents OT infrastructure typically faces. Here is the short version.
How to secure OT environments
NIST recommends defense in depth: several layers of controls and close cooperation between the IT and OT teams. The main goals:
- Limit logical access. Separate the OT network from the corporate one and the internet; use DMZs, firewalls, and separate authentication.
- Limit physical access. Locks, access control, and protection of devices against unauthorized hands.
- Harden the components. Patch quickly, turn off unused services, cut back privileges, and keep an audit trail.
- Detect incidents. Watch for failures, service outages, and anomalies before they turn into an incident.
- Keep running through failures. Redundancy and a graceful fall back to manual mode.
- Have a recovery plan. A rehearsed plan for responding and restoring after an incident.
MITRE ATT&CK for ICS as a threat map
MITRE ATT&CK for ICS is an organized catalog of the tactics, techniques, and procedures attackers use against industrial systems. It accounts for what makes OT different: safety, reliability, and operational constraints.
Each technique comes with a description, real incident examples, and matching countermeasures. It gives you a ready tool for threat modeling and planning defenses, instead of guessing what might happen.
Where to start
ICS and OT security is a young, fast-growing field. A good starting point is the NIST 800-82 guide and the MITRE ATT&CK for ICS catalog. Both are readable, and you do not need a narrow specialty to pull the first lessons out of them.
Running industrial systems and want to know where you are actually exposed? Book a free consultation. We will map the attack surface of your OT environment and tell you what to fix first.
Book a free consultation and we will check the attack surface of your OT environment and tell you what to fix first.