The Best Critical Infrastructure Cybersecurity Companies in 2026

Updated November 2026

Quick answer: The best critical infrastructure cybersecurity companies in 2026 include Asimily, Claroty, Nozomi Networks, Dragos, Armis, Forescout, Ordr, Fortinet, and Palo Alto Networks. Asimily fits operators that need one agentless inventory across remote facilities, need risks prioritized based on exploitability, and need segmentation simulated before it is enforced. Claroty and Nozomi Networks fit large OT programs, and Dragos fits operators that want threat intelligence and incident response.

A critical infrastructure security team must protect equipment that keeps power, water, transportation, and communications running, often at remote or lightly staffed facilities, without interrupting service. Controllers, SCADA servers, and field devices built to run for decades share networks with corporate IT, and the operations team holds an effective veto over any change that could stop a process.

The right partner for that environment finds every device across IT and OT, including those behind controllers (serially connected or not), identifies which exposures are exploitable in your network, and reduces the risk of an unplanned outage.

This guide covers what to test in infrastructure-ready platforms across energy, water, transportation, communications, and other sectors, a side-by-side view of the companies that appear most often in critical infrastructure evaluations, and where each one fits. Asimily publishes this guide. We include ourselves, and we describe every company based on its public positioning, how it approaches the problem, and our research and conversations with market participants.

The Best Critical Infrastructure Cybersecurity Companies at a Glance

Asimily appears first as the publisher; the order of the other companies is not a ranking.

Company	Primary Approach	Best Fit For
Asimily	Agentless visibility, ATT&CK-based exploitability analysis to separate risk from severity, and Segmentation Orchestration with Policy Simulation across IoT, IIoT, OT, IoMT, and IT	Operators that need to move from a unified asset inventory to enforced segmentation without interrupting service
Claroty	Cyber-physical systems protection: asset management, exposure management, network protection, secure access, and threat detection	Large operators standardizing OT security across many facilities that need secure remote access
Nozomi Networks	OT and IoT visibility, continuous monitoring, and threat and anomaly detection	Operations-led programs that value close ties to industrial automation vendors
Dragos	OT threat detection, industrial threat intelligence, and incident response services	ICS-heavy operators that prioritize threat intelligence and OT incident response via playbooks
Armis	Agentless asset intelligence and exposure management across IT, OT, IoT, and cloud	Enterprises standardized on ServiceNow workflows; cost-sensitive
Forescout	Device discovery, classification, and network access control across IT, OT, and IoT	Teams that want visibility and network access control from one vendor, independent of their switch vendor’s platform
Ordr	AI-driven device profiling and least-privilege policy across converged IT and OT	Converged networks that want policy applied through existing firewalls and switches
Fortinet	Firewalls and secure networking with OT protocol support	Operators consolidating network and security on one vendor
Palo Alto Networks	Next-generation firewalls, OT security services, and XDR across IT and OT	Enterprises extending an existing Palo Alto deployment to operational facilities

What to Look for in a Critical Infrastructure Cybersecurity Company

Critical infrastructure environments break assumptions that most security tools are built on: devices can’t take agents, facilities are spread out and often unstaffed, and a blocked connection can interrupt a public service. Use these criteria to test whether a platform was built for operational networks.

Visibility Across IT, OT, and Remote Facilities

An operator cannot protect what it has not listed, and many tools stop too soon. Many stop at the PLC, with no view of what sits behind it. Ask each vendor to show discovery of controllers, the field devices behind them (serially connected or not), and the systems around them in your own environment, captured agentlessly and safely against live operations, including at remote facilities with limited bandwidth. Sometimes this takes careful analysis of network traffic, and other times deep knowledge of the device vendor’s equipment plus active queries run only where they are safe. Ask what each remote facility needs in sensor hardware, and what it costs. The inventory should also cover the IoT and IT assets that may share the operational network, because those assets bridge the corporate network and the control network.

Prioritization by Exploitability Likelihood and Service Impact

A CVSS base score rates a vulnerability in general, without accounting for how the affected device is deployed in your network. Look for analysis that determines whether a vulnerability is actually exploitable on a specific device in your topology, plus the ability to weight safety and service continuity the way your operation values them. The output should be a short list of decisions, each with a documented reason for its ranking.

Enforcement You Can Prove Before You Deploy

Many operators already own a NAC, such as Cisco ISE, or segmentation-capable firewalls, yet segmentation projects stall because no one can confidently predict what a new policy will block. Tracing every flow by hand no longer scales across dozens of facilities. Look for a platform that generates policy in your NAC’s or firewall’s native format and previews its impact against real, observed traffic before anything is applied. Then it should keep that policy current as devices are added, moved, or patched. That preview is what earns approval from the people responsible for service and gives them the confidence to enforce.

Mitigation for Equipment You Can’t Patch

A controller that still runs a process does not get replaced because its vendor stopped issuing patches. Evaluate whether the platform recommends targeted mitigations, such as disallowing specific uses, segmentation, disabling unused services, or changing default credentials, that close the exposure and fit inside an existing maintenance window. Where a device supports automated patching, use it; that leaves fewer devices that need compensating controls.

Continuous Monitoring and Forensic Evidence

Threat detection should understand industrial protocols such as Modbus, DNP3, GOOSE, and BACnet, among many others, and flag insecure configuration drift alongside anomalous behavior. Ask whether you can capture packets from a specific device during an incident, so containment starts with evidence rather than reconstruction.

Compliance Evidence on Demand

Requirements vary by sector and region. U.S. operators often map controls to the NIST Cybersecurity Framework 2.0 (NIST), electric utilities in North America answer to NERC CIP, designated pipelines follow TSA security directives, community water systems complete AWIA risk assessments (EPA), EU operators in covered sectors answer to NIS2, and many align to ISA/IEC 62443 with zones and conduits clearly defined. Each asks for the same proof: a current device inventory, a documented risk assessment, and a record of which controls are enforced where. The platform should produce that record continuously rather than at audit time.

The Best Critical Infrastructure Cybersecurity Companies in 2026

1. Asimily

Asimily is the Proactive Cyber Asset Defense Platform for IoT, OT, IoMT, and IT. It unifies control networks, remote facilities, and corporate assets in one inventory so operators can find and isolate high-risk devices.

Agentless discovery pairs passive analysis of industrial protocols with targeted, low-impact queries to OT and IoT devices where safe, and the Asimily Edge collector software gathers data at remote facilities within a bandwidth limit you set. Its ATT&CK Analysis estimates the likelihood that each device can be compromised, weighted by factors such as network segmentation, patching status, and operational context.

Asimily’s Segmentation Orchestration builds and simulates policy, then applies it through your existing NAC and firewalls. Configuration Control detects drift and restores known good configurations, while native packet capture aids response. For unpatchable devices, Risk Simulator models the risk reduction of each mitigation before any change is made, and IoT Patching delivers firmware and password updates for supported device types. Deployment is cloud or on-premises.

Recognition: 2026 Merit Awards winner, and rated 4.9 out of 5 on Gartner Peer Insights (55 reviews, October 2026).

Best fit for: Operators needing visibility across every facility, risk-based prioritization, and pre-validated segmentation.

What to evaluate: Discovery at a remote facility, the documented reason behind each prioritized device, and Policy Simulation against your live traffic.

2. Claroty

Claroty focuses on cyber-physical systems across industrial, healthcare, and commercial environments. Its platform covers asset management, exposure management, network protection, secure remote access, and threat detection, and the company reports deployments at more than 8,000 sites across 40 industries.

Best fit for: Large operators that want a single OT security vendor and need secure remote access for third-party technicians.

What to evaluate: How deep discovery reaches into field devices at your facilities, and how network protection recommendations become enforced policy on your existing NAC and firewalls.

3. Nozomi Networks

Nozomi Networks provides OT and IoT asset inventory, continuous monitoring, and threat and anomaly detection for operational environments. Mitsubishi Electric completed its acquisition of Nozomi Networks in January 2026 (Business Wire), and the company lists ABB, GE Vernova, Schneider Electric, and Hitachi Energy among its partners.

Best fit for: Operations-led security programs that want monitoring closely aligned with industrial automation vendors.

What to evaluate: How findings are prioritized by exploitability on your specific devices, and what the platform does after an alert to reduce exposure.

4. Dragos

Dragos is an industrial cybersecurity specialist known for OT threat detection, threat intelligence on groups that target industrial environments, playbooks, and incident response services. Accenture’s majority investment in Dragos closed in September 2026 (SecurityWeek), and Dragos continues to operate under its own name.

Best fit for: ICS-heavy operators that prioritize threat intelligence and want an OT incident response partner on call if needed.

What to evaluate: Coverage of the IoT and IT devices that share the operational network, and how risk reduction moves from detection to enforced controls.

5. Armis

Armis Centrix is an agentless asset intelligence and exposure management platform spanning IT, OT, IoT, medical devices, and cloud. ServiceNow completed its acquisition of Armis in April 2026 (Verdict), and Armis Centrix remains available as a standalone product.

Best fit for: Enterprises that run IT and security workflows in ServiceNow and want device risk inside those workflows.

What to evaluate: OT protocol depth at operational facilities, and whether segmentation policy can be created, simulated, and maintained from the same platform.

6. Forescout

Forescout discovers and classifies devices across IT, OT, and IoT and pairs that visibility with policy enforcement and automated response, building on its network access control heritage. Its platform was renamed Forescout Vistaro in June 2026 (Forescout).

Best fit for: Teams that want device visibility and access control from one vendor rather than their switch vendor’s preferred platform.

What to evaluate: How the platform previews the impact of an enforcement action on an operational network before it is applied.

7. Ordr

Ordr’s AI Protect platform profiles devices by function, behavior, and communication patterns across converged IT and OT networks, and generates least-privilege policy that an analyst approves before it is applied through existing firewalls, NACs, switches, and wireless controllers.

Best fit for: Operators with converged IT and OT networks that want AI-assisted policy creation.

What to evaluate: How vulnerabilities are prioritized by exploitability on your devices, and which mitigation options exist beyond segmentation.

8. Fortinet

Fortinet’s Security Fabric combines firewalls, secure networking, endpoint protection, and centralized management, with OT protocol support and ruggedized hardware for industrial and remote facilities.

Best fit for: Operators consolidating networking and security on a single vendor.

What to evaluate: Where the device context and risk-prioritized policy that drive firewall rules will come from.

9. Palo Alto Networks

Palo Alto Networks extends its next-generation firewalls, segmentation, and Cortex XDR into OT environments to limit lateral movement between enterprise and operational networks.

Best fit for: Enterprises extending an existing Palo Alto deployment from the data center to operational facilities.

What to evaluate: Visibility into unmanaged field devices and how segmentation rules are validated against operational traffic before rollout.

Other Companies Critical Infrastructure Operators Consider

Cisco, TXOne Networks, Tenable OT Security, Microsoft Defender for IoT, and Darktrace also appear in critical infrastructure evaluations, often as extensions of an existing network or IT security investment or for specific needs such as legacy endpoint protection. Teams that need staff augmentation more than a platform often pair one of the companies above with a managed security provider that has OT experience.

Choosing the Right Fit for Your Operation

Start with the constraint that has stalled your program. A team that can’t see what is connected at its remote facilities should test discovery first and model the cost. If your partner’s most affordable sensor is overpowered for a small facility, it needlessly raises costs. A team with findings but no enforcement should test whether the platform can generate, simulate, and maintain policy on the NAC and firewalls it already owns, while a team that needs an incident response partner should emphasize threat intelligence and services. Run every pilot against your own traffic, and involve the operations owners who will approve any change.

[Related: OT Security: A Complete Guide to Protecting Operational Technology]

[Related: The Best Utility Cybersecurity Companies in 2026]

[Related: The Best Manufacturing Cybersecurity Companies in 2026]

Frequently Asked Questions About Critical Infrastructure Cybersecurity Companies

What Is the Best Cybersecurity Company for Critical Infrastructure?

The best fit depends on where your program is stuck. For operators that need agentless visibility across IoT, IIoT, OT, and IT, prioritization based on real exploitability through ATT&CK Analysis, and segmentation that is simulated against observed traffic before it is enforced, Asimily covers all three in one platform. Claroty, Nozomi Networks, and Dragos are OT specialists, and Fortinet, Palo Alto Networks, and Cisco extend network security into operational facilities.

What Are the 16 Critical Infrastructure Sectors?

In the United States, the Cybersecurity and Infrastructure Security Agency (CISA) lists 16 sectors (CISA): chemical; commercial facilities; communications; critical manufacturing; dams; defense industrial base; emergency services; energy; financial services; food and agriculture; government services and facilities; healthcare and public health; information technology; nuclear reactors, materials, and waste; transportation systems; and water and wastewater systems.

How Do Operators Segment OT Networks Without Interrupting Service?

They start with the highest-risk devices, validate each policy against real, observed traffic before it is applied, and roll changes out in stages, so operations owners see exactly which devices and connections would be affected. Asimily’s Policy Simulation does this, and Continuous Segmentation keeps NAC policies current as devices are added or removed. Many operators still schedule major network changes for planned maintenance windows, but enough simulation against observed traffic gives them the confidence to switch planned microsegmentation policies to enforcement.

How Do You Protect Remote Facilities With Limited Staff?

Treat each remote facility as a small network with its own inventory, a tested segmentation policy, and alerts that reach a central team, so staff do not need to travel for every question. Collect data locally, review it centrally, and keep configuration baselines so a known good state can be restored.

How Is OT Security Different From IT Security in Critical Infrastructure?

In critical infrastructure, an IT outage is an inconvenience; an OT outage can cut a public service. Because many controllers sit at remote facilities and can’t run agents or take routine patches, OT security depends on agentless visibility, compensating controls such as segmentation, and changes validated before they reach operations. The stakes differ too: a compromised controller at a water treatment plant or substation can put public health and safety at risk in a way a server in a data center rack rarely does.

See How Asimily Protects Critical Infrastructure

Asimily gives operators a complete, agentless inventory across IoT, OT, IoMT, and IT, a short list of the exposures that are actually exploitable, and segmentation policy simulated against real traffic before it is enforced.

Request a demo

Sources

• CISA, Critical Infrastructure Sectors
• NIST Cybersecurity Framework
• EPA, America’s Water Infrastructure Act risk and resilience assessments
• Mitsubishi Electric completes acquisition of Nozomi Networks (Business Wire, January 2026)
• Dragos completes acquisitions following Accenture deal (SecurityWeek, 2026)
• ServiceNow completes Armis deal (Verdict, April 2026)
• Forescout Vistaro platform rename (Forescout, June 2026)