In Operational Technology (OT), control is everything—over processes, production, and safety.
But what about access control?
Do you know exactly who can reach your critical systems right now? If not, you’ve already lost control—and your operations could be at risk.
As OT environments and OT networks become more connected and remote access more common, identity blind spots are opening the door to cyber-attacks.
Attackers are exploiting these gaps to reach operational systems, including distributed control systems—disrupting production, damaging equipment, and putting safety at risk.
What is operational technology?
Operational technology (OT) refers to the hardware and software that controls physical processes in industries such as manufacturing, utilities, transport, and critical infrastructure.
OT systems manage critical devices like industrial control systems (ICS), programmable logic controllers (PLCs), and physical devices that automate or monitor processes in the physical world.
Unlike IT systems, which focus on data and information flow, OT systems are embedded in physical operations—meaning a security breach can directly impact production, equipment, and safety.
Because OT systems were designed to prioritise uptime and reliability over security, understanding exactly who has access to them has become one of the biggest challenges for protecting operations today.
Access: The foundation of OT security
In operational technology, everything starts with access. Whether it's engineers configuring control systems, technicians running diagnostics, or suppliers connecting via remote access, every action depends on access being correct and controlled.
But access control in operational technology environments is often messy:
- Credentials linger after contractors leave.
- Remote access expands user reach—sometimes beyond what’s intended.
- Permissions drift over time, leaving operators with more access than they need.
Attackers gain access to OT networks through dormant accounts, over-permissioned users, or weak external connections.
Without full visibility into who can access what, you can’t be confident your OT environment is secure.
And it only takes one overlooked account to halt production or compromise safety.
Access sits at the heart of OT security. That’s why the Australian Cyber Security Centre’s (ACSC) six principles for OT Security place control and clarity over access at the foundation of operational resilience.
Access visibility enables the ACSC’s OT cyber security principles
The Australian Cyber Security Centre’s (ACSC) six principles for OT cyber security highlight the importance of control, clarity, and resilience in critical environments.Access visibility underpins each one—helping you reduce risk and protect operations.
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1. Safety is paramount
Access risk is a safety risk. A compromised login could disable supervisory control systems, disrupt processes, or trigger an unplanned shutdown—putting workers, equipment, and critical services at risk.
Would you send your team on-site during a cyber incident, knowing an attacker could still have remote access to safety-critical control systems?
Knowing—without question—who controls those systems in real time allows you to prevent unauthorised actions before they endanger your people or disrupt operations.
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2. Knowledge of the business is crucial
Understanding OT processes is essential—but knowing who can interact with them is just as important.
Access visibility connects the two—helping those responsible for uptime, production, and security see exactly who can operate or alter critical processes.
Critical infrastructure operators must ensure their teams understand both the industrial control systems running core processes and the access pathways that could expose those systems to threats.
Have you identified the minimum OT equipment and personnel required to keep core services running if systems fail? Knowing who can access those critical components is just as vital as understanding the processes themselves.
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3. OT Data is extremely valuable and needs to be protected
Configuration files, system blueprints, and control data are prized targets for attackers. This information rarely changes, meaning it can be exploited for years if compromised.
Control systems and data acquisition tools are often targeted by attackers looking to disrupt operations or steal critical configurations.
Are your OT configuration files stored on personal laptops, in emails, or within the corporate IT network? Controlling who can access this data is as crucial as securing your control systems themselves.
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4. Segment and segregate networks
Segmentation only works if access follows the same rules.
When credentials cross-industrial networks and IT systems, network separation is undermined.
Would you know if an engineer’s credentials gave them unintended access across both OT and IT systems? Access visibility exposes these hidden links—helping you ensure network security defences hold firm.
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5. The supply chain must be secure
Third-party access often starts as a necessity—but without careful oversight, it can quietly become a long-term risk. Vendor, contractor, and managed service provider (MSP) accounts are often left active long after work is completed—creating hidden vulnerabilities.
A supplier who needed temporary access last year could still have credentials today—would you know?
Continuously monitoring external access to your OT environment ensures you stay in control—knowing exactly who’s connected and whether they should be.
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6. People are essential for OT cyber security
Operators, engineers, and technicians are your frontline defenders.
But they can only act with confidence if they trust that access is tightly controlled.
What if an operator notices a remote session controlling a system—would they know if it was legitimate or malicious? Real-time visibility gives teams the clarity to identify unusual activity early—and the assurance that systems are secure.
Trusted partners for access visibility and OT security
Gathid, a trusted partner of The Missing Link, gives you the visibility to see exactly who can access your OT systems. The Missing Link ensures you can act—reducing risk and aligning access with operational resilience.
Together, we help you:
- See your complete OT and IT access landscape.
- Identify dormant, excessive, or risky permissions.
- Align access controls with safety, uptime, and operational resilience.
Visibility into identity and access supports broader cyber security requirements, helping organisations secure their systems while ensuring OT security aligns with operational resilience.
Because securing operational technology starts with knowing who has access.
Take control of access before it becomes a problem
As OT environments evolve, identity risk is becoming one of the biggest threats to operational security. Access visibility is the foundation of resilience – because securing OT starts with knowing who has access.
Take control of access before it controls you. Speak to our experts today to strengthen your OT security and reduce risk with access certainty – because securing OT starts with knowing who has access.
