Topic starter
08/06/2026 3:59 pm
TL;DR: Operational technology environments are shifting from isolated systems to connected IT, IoT, and cloud architectures, which expands attack surface and raises the need for continuous verification, just-in-time privilege, and monitored remote access, according to SSH Communications Security. The governance problem is no longer network location, but whether every machine, vendor, and session can be trusted only for the exact task and duration required.
Editorial analysis by NHI Mgmt Group, based on content published by SSH Communications Security: “Zero Trust Strategies for Securing OT and Critical Infrastructure”.
Key questions
Q: How should security teams apply zero trust to OT without disrupting operations?
A: Start with identity inventory, least privilege, and segmentation that respects safety and uptime.
Q: Why do standing privileged accounts create compliance and security risk?
A: Standing privileged accounts keep high-risk access available even when no task requires it.
Q: What breaks when OT remote access still relies on reusable passwords or SSH keys?
A: Reusable secrets create a durable entry path that survives the job they were meant to secure.
Practitioner guidance
- Eliminate standing OT administrator access Replace persistent privileged accounts with task-scoped elevation that is approved per session and revoked automatically after the maintenance action ends.
- Issue ephemeral credentials for remote maintenance Move password and SSH key based access to short-lived certificates or equivalent ephemeral authentication so remote support sessions do not reuse the same secret across jobs.
- Unify vendor access with PAM governance Treat third-party OT support as part of the same privileged access policy set as internal administration, including MFA, encrypted tunnels, session monitoring and approval records.
Bottom line: OT zero trust fails when teams rely on network location instead of governing each identity and session for a specific task.
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This topic was modified 2 days ago by NHI Mgmt Group
08/06/2026 5:20 pm
OT zero trust has become an identity governance problem, not just a network design problem. Once industrial environments connect to IT, IoT and cloud services, location can no longer be the main trust boundary. The real question is whether every identity, device and session is governed for the exact task it must perform, then withdrawn immediately after use. That shifts OT security from static segmentation to continuous lifecycle control.
A few things that frame the scale:
- 90% of IT leaders say properly managing NHIs is essential for a successful zero-trust implementation, according to the Ultimate Guide to NHIs.
A question worth separating out:
Q: How do IAM and PAM teams govern third-party access in OT?
A: They should use one control model for internal administrators and external vendors, with MFA, encrypted tunnels, least privilege and session recording applied consistently. The key is to tie access to a specific task and retire it as soon as that task is complete.
👉 Read our full editorial: Zero trust for OT access is now an identity governance problem
This post was modified 2 days ago by NHI Mgmt Group