OT Cybersecurity KPIs: Patch, Backup, Detection, Segmentation and Remote Access Benchmarks

Use a benchmark as a first reference point, not as a target. OT security programs start from very different places, so the ranges below are most useful for spotting the gap that matters most on your highest-value lines.

Every figure here shows its basis. A superscript number links to a public source in the Sources list at the end, such as NERC reliability standards, CISA guidance or Mandiant's incident data, and the sentence states that source's scope. A figure marked no cited source is kept exactly as originally published because none of the public documents reviewed for this guide states it, so treat it as illustrative.

At a glance

Patch compliance

Track patch compliance first, because it correlates with nearly every downstream KPI. Typical OT plants run 55 to 70 percent of critical assets patched within their SLA window no cited source.

World-class programs hold 90 to 95 percent against a 30-day window for criticals and 90 days for the rest no cited source. The gap is rarely tooling; it is change windows.

Regulated OT sets a clock of its own. In the bulk electric sector, NERC CIP-007-6 requires utilities to evaluate new security patches at least every 35 calendar days, then apply each applicable patch or file a dated mitigation plan within 35 days of that evaluation⁴.

How to measure

• Count critical assets patched within their SLA window over critical assets that need the patch.
• Keep the denominator clean, limited to assets that actually need each patch.
• Set the SLA window by severity and report each window separately.

What moves it

• Batching patching into scheduled maintenance outages instead of ad hoc requests, which moves plants 15 to 20 points in two quarters no cited source.
• Agreed change windows with operations.

Measure it with the Patch Compliance Rate calculator.

Backup coverage and tested recoverability

Backup coverage and recoverability separate a bad day from a catastrophe. Typical coverage of critical OT assets sits at 60 to 75 percent, and world-class is 95 percent or higher with quarterly restore tests no cited source.

The KPI that matters is tested recoverability, not coverage alone: aim for 100 percent of tier-one assets restore-tested within 90 days no cited source. The recovery time objective (RTO) for a critical line should be under 8 hours world-class, versus the 24 to 72 hours typical after an OT ransomware event no cited source.

Published minimums for restore testing are well below a quarterly cadence. CISA's cross-sector performance goals call for testing backups and recovery no less than once per year³, and NERC CIP-009-6 requires testing a representative sample of recovery information at least once every 15 calendar months⁵.

How to measure

• Count critical OT assets with a current backup over all critical OT assets.
• Count tier-one assets with a successful restore test in the window, separately from coverage.
• Document an RTO for each line and compare it with actual restore times.

What moves it

• A scheduled restore-test program rather than coverage alone.
• Tiering assets so the critical line's controllers are restored first.

Track coverage with the Backup Coverage Rate calculator, and size what a slow recovery costs with the Ransomware Exposure Cost calculator.

Detection and response time

Detection and response times are the headline resilience metrics. Mean time to detect (MTTD) in OT environments is often measured in days, because passive monitoring is missing.

Across industries, intrusions typically go unnoticed for more than a week¹. Mandiant's M-Trends 2025, covering its 2024 incident-response investigations in all sectors rather than OT alone, puts global median dwell time at 11 days, up from 10 days in 2023¹.

How an intrusion is found matters. In those investigations, median dwell time was 10 days when the organization found the activity itself, 26 days when an outside party told it, and 5 days when the attacker announced itself, usually with ransomware¹.

World-class MTTD is under 1 hour with proper network sensors no cited source. Mean time to respond (MTTR), from detection to containment, should target under 4 hours world-class versus 12 to 48 hours typical no cited source.

How to measure

• Time detection from first malicious activity to the alert.
• Time response from detection to containment.
• Track the share of OT network segments with passive monitoring alongside both.

What moves it

• Monitoring coverage, which is almost the whole MTTD lever.
• Instrumenting 90 percent of OT network segments, which collapses MTTD from days to minutes without touching headcount no cited source.

Put a dollar figure on each hour of detection and response with the OT Downtime Cyber Loss calculator.

Vulnerability backlog burn-down

Vulnerability backlog burn-down tells you whether you are gaining or losing ground. A healthy program remediates at least 30 to 40 percent of open findings per quarter against steady inflow no cited source.

That pace keeps mean time to remediate criticals under 30 days, while typical plants sit at 90 to 180 days with a growing backlog no cited source.

For comparison from IT, CISA's BOD 22-01 gives U.S. federal civilian agencies two weeks to remediate known exploited vulnerabilities, or six months for those with a CVE ID assigned before 2021⁶. Treat it as an IT reference point, not an OT rule.

How to measure

• Watch the backlog trend, not the absolute count.
• Read a flat or rising backlog as remediation throughput below inflow.
• Plot the burn-down curve quarter by quarter.

What moves it

• A target that remediation exceeds discovery by 10 percent each quarter no cited source.
• Remediation work scheduled into maintenance outages, like patching.

Segmentation maturity

Segmentation maturity is a structural KPI that caps your blast radius. Typical plants have 30 to 50 percent of critical assets properly zoned, and world-class is 85 percent or higher, aligned to Purdue-model levels no cited source.

How to measure

• Count OT assets behind a monitored conduit over all OT assets.
• Treat assets flat-networked with IT as unzoned.

What moves it

• Working cell by cell rather than all at once.
• Enclosing the zones that control the highest downtime-dollar lines first.

Rank zones with the OT Asset Risk Score calculator. Each zone you enclose shrinks the probability inputs behind your Network Segmentation ROI case.

Remote access hygiene

Remote access hygiene is a fast-moving KPI with clear targets. Benchmark the share of remote and vendor connections using multi-factor authentication (MFA) plus session recording: world-class is 100 percent, a figure the cited standards support for MFA only^{2, 3}, and typical is 40 to 60 percent no cited source.

In the bulk electric sector, NERC CIP-005-7 requires MFA for all Interactive Remote Access sessions to high-impact systems and to medium-impact systems with external routable connectivity². CISA's cross-sector performance goals say OT systems should enable MFA on remotely accessible accounts³. Neither requires session recording.

The long tail of shared vendor credentials is where breaches originate. Target zero standing vendor accounts, with just-in-time access granted per session.

How to measure

• Count remote and vendor connections with MFA and session recording over all remote connections.
• Score each connection for risk and drive the average below 3 out of 10 no cited source.
• Block or remediate connections scoring above 6 within 30 days no cited source.

What moves it

• Retiring shared vendor credentials.
• Just-in-time access granted per session.

Insurance readiness

Insurance readiness has quietly become a KPI because failing it costs real money. Insurers benchmark MFA coverage, tested backups, endpoint detection and response (EDR) on Windows assets, and segmentation. Meeting the common threshold set of MFA everywhere, 90 percent backup coverage and a documented incident response plan typically earns 10 to 25 percent premium reduction no cited source and avoids coverage exclusions.

How to measure

• Track your control posture against the underwriting checklist quarterly.
• Record each gap with an owner and a close date before renewal.

What moves it

• The same levers as the KPIs above, especially MFA, tested backups and segmentation.
• Evidence ready before renewal, so it is a formality rather than a scramble that ends in a higher deductible or a declined claim.

Estimate your exposure with the OT cyber risk calculators.

Roll the KPIs into one scorecard

Review one scorecard monthly, weighted by downtime-dollar impact so the numbers drive resourcing. Most plants start 20 to 30 points behind on each target no cited source.

Pick the two KPIs tied to your highest-value lines and move them first. Let the OT Asset Risk Score ranking decide the sequence rather than chasing every metric at once.

How to build your own baseline

• Build a clean asset inventory first, since every coverage KPI divides by it.
• Write down each KPI's definition, window and denominator and keep them fixed.
• Collect a few quarters of data before you set targets.
• Compare against your own trend first and published ranges second.
• Weight each KPI by the downtime cost of the lines it protects.