How should energy organisations secure remote access across IT and OT environments?

Why This Matters for Security Teams

Remote access in energy is not just a convenience problem. It is a control-plane problem that affects availability, safety, and recovery time when something fails. Broad VPN access, shared jump hosts, and standing credentials can turn a single contractor session into a route across IT and OT segments. Current guidance from NIST SP 800-53 Rev 5 Security and Privacy Controls supports stronger identity, access, and monitoring controls, but the real challenge is applying them where legacy engineering tools were never designed for modern trust decisions.

Security teams often get this wrong by treating OT remote access as an exception to standard access policy rather than a high-risk access path that deserves stricter control. When operators, vendors, and maintainers all need different levels of access, the policy must follow the task, the asset, and the session, not just the user account. That is especially important when remote support touches controllers, historians, engineering workstations, or cloud-connected operational platforms. In practice, many security teams encounter remote access risk only after a maintenance account, vendor tunnel, or mis-scoped privilege has already been used to reach systems that were assumed to be isolated.

How It Works in Practice

Effective remote access for energy organisations starts with identity-centric access enforcement. The user or service must prove who it is, the device must be assessed, and the session must be limited to the approved resource. That usually means replacing broad network reach with per-application, per-asset, or per-session access paths. In OT environments, this often requires an access broker, a hardened remote support workflow, or a segmented jump path that can inspect context before granting entry.

Practitioners should separate human administrator access from non-human access used by service tools, scripts, or managed integrations. The OWASP Non-Human Identity Top 10 is useful here because many energy environments now depend on machine credentials, API keys, and automation accounts for monitoring and orchestration. Those identities need inventory, ownership, rotation, and logging just like human users do.

• Require MFA for remote human access, then bind access to device health, location, and session risk.
• Use just-in-time approval for privileged tasks instead of permanent vendor accounts.
• Restrict each session to a named system, protocol, or command path where possible.
• Log commands, file transfers, and screen activity for high-risk maintenance sessions.
• Review non-human identities, certificates, and secrets with the same discipline as privileged user accounts.

Remote access also needs monitoring that can distinguish normal maintenance from suspicious movement. Correlating access events with asset criticality, change windows, and alerting helps operators spot unusual use of trusted pathways before it becomes a safety or outage issue. These controls tend to break down in brownfield OT environments with unmanaged vendor dependencies because older systems cannot enforce per-session policy, posture checks, or modern telemetry.

Common Variations and Edge Cases

Tighter remote access often increases operational friction, requiring organisations to balance faster maintenance response against stronger approval and logging. That tradeoff is real in energy operations, where outage windows are short and field engineers may need access from constrained sites or third-party support centres. Best practice is evolving, but there is no universal standard for every legacy plant architecture.

One common edge case is emergency access. Break-glass accounts may still be necessary, but they should be rare, monitored, and separately governed rather than treated as routine fallback. Another is remote access for OEMs and integrators who need temporary support across multiple assets. Those sessions should be time-bound, scoped, and tied to a specific work order. Where data flows between IT and OT, access control should be paired with network segmentation and strict asset inventory so that remote users cannot pivot from a support portal into safety-critical systems.

Energy organisations operating under critical infrastructure obligations should also align remote access governance with incident response and resilience planning, because access pathways are often the first route attackers probe during disruption events. The right question is not whether remote access exists, but whether each access path is provably necessary, constrained, and observable when it is used.

Related resources from NHI Mgmt Group

• Why does secure remote access matter more in OT than in standard IT environments?
• How should organisations secure machine access in OT environments without slowing operations?
• How should manufacturing teams secure access across IT and OT environments?
• How can organisations secure third-party privileged access in hybrid environments?