Asset Inventory Guidance from CISA and BSI

The Cybersecurity and Infrastructure Security Agency (CISA), in collaboration with the German Federal Office for Information Security (BSI) and other organizations, has published recommendations for establishing and maintaining asset inventories in critical infrastructure environments. This marks a significant shift in perspective regarding asset management. It is now regarded not only as a technical best practice but also as a regulatory expectation and a risk management necessity.

Categorization by Criticality

Concerning the energy sector, the guidance endorses every OT asset to be classified by criticality:

High Criticality

Protection relays, DCS/SCADA cores, critical PLCs, power transformers, breakers, switchgear, UPS/backup power: These assets demand the strongest security measures and prioritized patching.

Medium Criticality

RTUs, gateways, PMUs, data historians, control system switches/routers, and control room environmental controls: These assets require structured monitoring and defined update plans.

Low Criticality

Supporting systems such as lighting, non-critical security, administrative workstations, and ambient sensors: These assets require only basic controls and inventory documentation.

Required Inventory Fields

In addition to categorization, federal agencies outline mandatory data fields for each asset, with a defined order of priority. The following are examples of this classification:

High-priority Fields

Asset names/numbers, role/type, IP/MAC address, hostname, vendor, model, and physical location

Mid-priority Fields

Firmware/software version

Low-priority Fields

Serial number, description, and lifecycle metadata

The Asset Inventory Guidance by CISA, BSI, and Other Organizations in the Industry Highlight Mandatory Steps for Power Grid Providers

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Implications for Operators

The new guidance draws attention to two key points:

Accountability

Maintaining a structured asset inventory is now inseparable from regulatory compliance, incident response readiness, and cyber resilience.

Automation

Manual processes promise to be increasingly insufficient in the years to come, and automation is therefore strongly recommended.

How OMICRON
Supports Compliance

With StationGuard grid operators can establish an asset management that is both automated and fully aligned with CISA/BSI requirements. The solution combines:

Passive Detection &
Active Interrogation

Passive detection and active IEC 61850 MMS interrogation to populate all high-priority fields automatically.

Detailed
Documentation

Criticality assignment and change documentation to meet regulatory accountability requirements.

Direct Alarm Mapping

Direct vulnerability correlation (via GridOps) to map each asset to relevant security advisories, enabling proactive patch and mitigation planning.

By integrating asset management, vulnerability management, and criticality mapping, StationGuard provides CISOs with an audit-ready foundation for regulatory compliance and a practical tool to improve operational resilience.

Resources

21. August 2025