Introduction

Operational technology environments face a unique security challenge. Unlike IT systems, where a breach primarily risks data, an OT intrusion can halt production, disable critical infrastructure, and threaten public safety. As industrial networks converge with IT and remote support becomes standard, privileged access has become the primary entry point for attackers. This post explores why traditional PAM falls short in OT and what a modern, agentless approach looks like.

What Happened

Recent industry data underscores the stakes. Unplanned industrial downtime costs an estimated $2.3 million per hour, ransomware attacks start through third-party access 41% of the time, and it takes an average of 96 days to remediate an ICS compromise. These numbers reveal a recurring pattern: whenever vendor accounts, contractors, or shared credentials are left unmanaged, the entire plant becomes vulnerable. The root cause in most serious OT incidents is the same—uncontrolled privileged access.

Why This Matters

OT environments inherit weaknesses that IT tools were never designed to address. Many facilities run four or more remote access solutions simultaneously, each with its own credentials and no central governance. Hardcoded passwords, factory-default PLC logins, and shared service accounts create accountability gaps. Ungoverned VPNs give contractors broad network access that persists long after work ends. Without least privilege enforcement, a single compromised credential can spread laterally across the entire operational network. Compounding these issues, many OT sites are geographically dispersed, and IT and OT teams often operate in silos, leaving privileged access ungoverned on both sides.

Key Takeaways

An effective OT PAM program adapts core principles to industrial realities. Five capabilities form the foundation: controlled vendor access through a secure gateway with just-in-time, time-limited sessions; agentless connectivity that respects certified systems and avoids reboots; just-in-time access that eliminates standing privileges; comprehensive session recording and monitoring with automated anomaly detection; and centralized credential management that discovers, vaults, and rotates passwords, keys, and certificates across distributed assets. These measures directly address the attack vectors most commonly exploited in OT breaches.

  • Controlled vendor access with JIT time-limited sessions
  • Agentless connectivity via RDP, SSH, VNC, and Telnet
  • Just-in-time privilege elimination for all users
  • Full session recording and automated anomaly alerts
  • Centralized vault for passwords, keys, and machine credentials

Conclusion

OT environments cannot afford the downtime that follows a compromised credential. Securing privileged access doesn't require re-architecting your plant or replacing legacy systems. It means ensuring the right people have the right access, for the right amount of time, with full visibility into every action. By adopting an agentless, just-in-time PAM approach, organizations can close the gaps where OT attacks thrive, stay compliant with NERC CIP, IEC 62443, and NIST 800-82, and protect critical infrastructure from disruption.