While the drive to merge IT and OT systems in manufacturing certainly boosts efficiency, this integration creates significant new cybersecurity vulnerabilities. Real-world attacks, ranging from production-halting ransomware to direct manipulation of machinery, painfully illustrate that traditional IT security measures often miss the mark in OT settings. Different environments demand different approaches. Recognizing this gap, industry-specific frameworks like ISA/IEC 62443 are becoming essential tools for protecting industrial operations. Privileged Access Management (PAM) plays a critical role here. Far from being just another checkbox, controlling privileged access is truly fundamental to managing the unique risks inherent in OT.

Understanding the ISA/IEC 62443 approach
Priorities within OT systems look quite different from the usual IT concerns. Operational technology heavily emphasizes safety, uptime (availability) and the trustworthiness of data and processes (integrity), often ranking confidentiality lower. This focus exists for good reason: any small disruption, unauthorized adjustment, or safety failure in an OT environment can cascade into major operational problems, significant financial loss and potentially physical harm.

To navigate these specific challenges, the ISA/IEC 62443 standards provide a structured, risk-aware methodology tailored for OT. Some core ideas include:

• Zones and conduits: Breaking the network into logical chunks (zones) and carefully controlling the connections between them (conduits) helps limit and watch data flow.
• Security levels (SL): These levels, from basic (SL1) to highly protected (SL4), define how strong security needs to be for different zones based on the risks involved.
• Foundational requirements (FR): ISA/IEC 62443 outlines seven key areas, like controlling who can log in, what they can do once logged in and restricting data movement.

Putting these requirements into practice demands real, practical security steps, especially when it comes to controlling and monitoring privileged access.

Why PAM is so important for OT security
So, how does PAM specifically help tackle OT security headaches, especially in line with ISA/IEC 62443? It hits several key areas:

• Dealing with shared logins: Lots of OT systems still use generic or shared accounts, making it impossible to know who did what. PAM tools fix this by storing these credentials securely, tracking their use and linking every action back to a specific person. This vastly improves accountability.
• Managing widespread privileged access: In OT, engineers, maintenance crews and outside vendors often need privileged access. PAM pulls control of this access into one place, making it easier to see who has what permissions and enforcing strict rules.
• Securing vendor remote access: Letting third parties connect remotely is often necessary for support, but it opens a risky door. PAM systems offer fine-grained control. Vendors can be allowed access only during specific times, to specific machines, while everything they do is watched and recorded. This is much safer than older VPN methods.
• Handling hardcoded credentials: It’s common for passwords or API keys to be embedded directly in applications or automation scripts – a major vulnerability. PAM keeps these secrets safe, only providing them when needed, instead of storing them insecurely.
• Acting as a gateway for OT protocols: Many older or specialized OT protocols (like Modbus, Profinet, S7) weren’t built with security in mind. PAM solutions can act as secure gatekeepers, applying strong access rules and keeping audit trails even for these tricky systems.

Making PAM work in OT
Getting PAM into an industrial setting isn’t always easy. You might face pushback, deal with old equipment and absolutely cannot afford downtime. Here are some practical ways to make it work:

• Choose agentless options: Look for PAM setups that use gateways or proxies. This avoids needing to install software directly on sensitive or old OT devices.
• Roll it out in phases: Don’t try to do everything at once. Start with less critical systems or a specific problem, like securing vendor access. Build on success.
• Minimize impact: Make sure the PAM system itself doesn’t slow things down or become a single point of failure that could halt operations.
• Get everyone talking: Good communication between the OT experts, IT teams, and security folks right from the start is key. This ensures the PAM solution respects how things actually work on the factory floor.

Wrapping up
Today’s factories and industrial plants are more connected than ever, making strong cybersecurity non-negotiable for staying safe and operational. Standards like ISA/IEC 62443 give us the blueprint. But blueprints need tools to become reality, and that’s where Privileged Access Management becomes essential. By locking down who can access sensitive OT systems, tracking what they do and managing critical passwords securely, PAM makes a massive difference in security. For manufacturers serious about protecting their operations, PAM isn’t just about ticking a compliance box – it’s a smart move to safeguard their future.

Marcelo Pinto is a Certified Information Systems Security Professional, currently serving as R&D and IT operations lead at Segura. He integrates expertise in IT infrastructure management, advanced networking, High-Performance Computing, and artificial intelligence initiatives to deliver solutions in complex technological environments.