What Is OT/ICS Asset Inventory and Why Is It the Foundation of a Cybersecurity Program?

Cybersecurity is no longer just an IT concern; it's a critical component for safeguarding operational technology (OT) and industrial control systems (ICS) as well. Why? A breach could lead to not just data loss but also severe disruptions, safety hazards, and financial setbacks. Given these high stakes, understanding the need to safeguard these critical infrastructures becomes crucial. This article delves into the concept of OT and ICS asset inventory – what it is, why it's essential, and how it serves as the cornerstone for a robust cybersecurity program.

What Are OT Assets?

OT assets are the hardware and software components that make up an OT environment. These assets are instrumental in the control of physical processes, distinguishing them from IT infrastructures, which primarily handle data processing and business applications. OT assets comprise a wide range of components, including sensors, actuators, controllers, networking equipment, and the software that operates on these devices. Their primary purpose is to monitor and govern real-time operations across various industrial domains like manufacturing plants, energy grids, and water treatment facilities.

What Is an OT Asset Inventory?

OT asset inventory refers to the systematic collection, cataloguing, and management of all technological systems within an ICS environment. The scope is extensive since it is not just a catalogue of hardware and software; it's an actionable repository of information.

Importantly, adding technological systems to the list is not a one-time activity but an ongoing process. As new ones are added, or existing ones are modified or decommissioned, the list needs to be updated. This dynamic nature makes it a foundational element for any digital safety initiative because it enables organisations to adapt to changes in their systems and to evolving external threats.

What Are the Components of a Comprehensive ICS List?

This table provides a more in-depth understanding of the various components of an ICS list and their purposes.

Component	Details	Purpose
Hardware
IP Addresses	Document every networked device's IP address	Asset tracking and management. Crucial for network configuration and incident response.
Devices	Record serial numbers	Unique identification for tracking, warranty claims, and targeted maintenance.
Make/Model	Manufacturer and model details	Understanding device capabilities, limitations, and known vulnerabilities for risk assessment.
Key Statistics	Metrics like uptime, performance data, and error rates	Useful for predictive maintenance, troubleshooting, and performance optimisation.
Software
Operating System	Document the OS version	Critical for vulnerability assessment; helps in applying relevant patches and updates.
Firmware	Record firmware versions	Identifying risks and ensuring that devices are running the most secure, updated version.
Application Software	List all software applications, versions, and patch levels	Essential for vulnerability management and compliance; helps in identifying outdated software.
Users and Accounts
Dormant Accounts	Identify inactive accounts	Reduce safety risk by deactivating or removing accounts that are no longer in use.
Shared Accounts	Document and justify shared accounts	Monitoring for unauthorised or suspicious activity; shared accounts should be limited and justified.
Local/Admin Accounts	List local accounts with administrative privileges	Identifying potential points of entry for attackers. Helps in implementing least privilege principles.
Network Details
Connections	Document all network connections, wired or wireless	Building a secure network architecture and helping in monitoring and controlling data flow.
Paths	Document data flow paths	Understanding how data moves within the system for better security planning and incident response.
Protections in Place	List existing firewalls, intrusion detection systems, etc.	Evaluating the effectiveness of current safety measures and help in planning for additional protections.
Additional Info
Location	Physical or virtual location	Important for compliance with location-specific regulations and for risk assessment.
Criticality	Assess and document the criticality of the asset in business processes	Helps in prioritising security measures and resource allocation based on business impact.
Backup Status	Information on backup frequency and location	Essential for disaster recovery planning; helps in quick restoration of services in case of incidents.

Why Is OT/ICS Asset Inventory the Foundation of a Cybersecurity Program?

The importance of listing your industrial technological infrastructure can be summed up in the phrase, "You can't safeguard what you can't see". Without a comprehensive OT security assessment understanding of your systems, where they are located, and how they interact, it's nearly impossible to safeguard them effectively.

A well-maintained inventory is a cornerstone for risk assessment and vulnerability management. It allows you to identify the 'weakest links' in your system – be it outdated firmware, a dormant user account, or a misconfigured firewall. Once these weaknesses are identified, they can be prioritised based on their criticality and impact on the business.

For example, a susceptibility in a system controlling an important manufacturing process would be prioritised over a non-critical administrative system. This is only possible when you have a complete picture of your assets and their roles within the organisational processes.

What Are the Steps Involved in Conducting an OT Asset Inventory?

This process involves several key steps to ensure that hardware and software are accounted for, classified, and documented. Here's a breakdown:

1. Identification 
   The first step is to identify every piece of hardware and software that constitutes the OT environment. This could range from sensors and actuators to PLCs (Programmable Logic Controllers), SCADA (Supervisory Control and Data Acquisition) systems, and networking equipment like switches and routers that facilitate communication between OT systems.
2. Classification
   After identification, they should be categorised based on various parameters such as their criticality to operations, function, and location. For example, a controller managing a sensitive production line may be classified as 'highly critical', while a sensor monitoring ambient temperature might be 'less critical'.
3.  Mapping
   Understanding how the various ICS interconnect is essential for both operational efficiency and security. This involves creating a network map that shows how each infrastructure is connected and interacts with others, which can help in identifying potential vulnerabilities and planning for contingencies.
4. Documentation
    All the information gathered should be recorded in a central repository. This documentation should include technical specifications, location, function, and any other relevant data. A centralised list aids in quick decision-making, especially during incidents that require immediate action.
5. Maintenance
   Since assets may be added, removed, or modified, the inventory needs to be updated regularly. Scheduled reviews should be conducted to ensure that the list remains current and accurate.
   By following these steps, companies can gain a comprehensive understanding of their OT landscape. This not only aids in operational efficiency but also significantly enhances the organisation's ability to secure its assets against potential threats.
   

Benefits of a Robust ICS Asset Inventory

Maintaining a robust ICS list offers a multitude of benefits for organisations. Here are some of the key advantages:

• Improved Security: As also highlighted above, a comprehensive list allows for the identification and prioritisation of vulnerabilities. This information is crucial for implementing targeted safety plans, such as firewalls, intrusion detection systems, and data encryption, thereby strengthening your ICS technology environment against cyber threats.
• Compliance: Organisations, especially those in sensitive sectors like energy, healthcare, and manufacturing, have a significant concern regarding compliance. Failure to adhere can result in huge fines and reputational damage, making listing your technological systems an important component in governance and compliance strategies.
• Maintenance and Upgrades: Knowing the age, condition, and performance metrics of your critical ICS infrastructure helps in scheduling timely maintenance, thereby reducing the risk of unexpected downtime. It also aids in making informed decisions about when to upgrade systems, ensuring that you're getting the most out of your investments while maintaining peak performance.
• Resource Management: Understanding the capabilities and limitations of each asset allows for better planning and utilisation. For example, underutilised technology can be repurposed or decommissioned, freeing up resources for more essential operations. This level of insight is necessary for optimising functional efficiency.
• Financial Management: From an economic perspective, an asset inventory aids in budgeting and cost control. It provides a clear picture of where resources are allocated, helping to identify areas where cost savings can be realised. Additionally, it assists in capital planning by offering data on age, performance, and maintenance history, thereby informing decisions on asset replacement or refurbishment.

What Are Some Common Challenges Associated With Listing Your OT Asset?

Here are some of the common challenges associated with listing your OT asset:

• One of the most prominent issues is the limited visibility. Suppose the technological infrastructures are dispersed across multiple locations, including remote sites and different geographical regions. In that case, it will be difficult to identify, locate, and manage them effectively, leading to incomplete inventories that can compromise security.
• Another obstacle is the lack of standardisation. OT environments frequently consist of assets from various manufacturers, each with different makes, models, and configurations. This diversity complicates the process of creating a unified inventory and poses challenges in applying consistent security policies and controls. As a result, the risk of vulnerabilities and breaches increases.
• Limited documentation heightens these challenges. Some technological systems often come with little or outdated guides, making it difficult to understand their function, interconnectivity, and dependencies. This lack of information not only hinders the creation of a comprehensive checklist but also impacts the ability to assess risks and vulnerabilities accurately.
• Lastly, specialised expertise is often lacking within organisations because the task demands a unique blend of skills in both OT and IT. Without this expertise, companies may struggle to create an asset inventory that accurately captures the complexity and nuances of their OT environment, leaving them vulnerable to a range of safety risks.

Microminder Can Help With Inventory and Securing Your OT Assets

Are you ready to safeguard your ICS from threats? Microminder is the right partner to work with. We are a first-rate cybersecurity consultancy agency providing all-round offensive and defensive security solutions for small and large businesses globally.

Our services give you complete visibility into your systems, making it easier to protect them from attackers. Hence, with a focus on delivering actionable insights, we will help with OT assets inventory in the following ways: 

• We leverage our OT and IT experts to help develop a comprehensive safety plan, protecting your industrial infrastructure from cyber threats.
• Our experts will use cutting-edge tools and techniques specifically for OT asset discovery to monitor network traffic and provide real-time updates.
• We assist with risk assessment and vulnerability management to identify weak points and recommend targeted security measures.
• Also, we use our experience in compliance to ensure that your asset checklist meets the standards required by industry regulations, helping you avoid legal repercussions.

Aside from that, we provide bespoke penetration testing, compromise assessments, red teaming, architecture reviews, dark web monitoring and cloud security posture management as part of our wider digital security services.

Ready for comprehensive OT assets security?

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• Get in touch with our team here.
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Conclusion

A well-maintained OT/ICS asset inventory serves as the foundation for a robust cybersecurity program, enabling vulnerability identification and protection. Although challenges like limited visibility and lack of standardisation exist, partnering with experts like Microminder can help organisations create a comprehensive asset list and address these issues. Their services encompass asset discovery, risk assessment, compliance adherence, and advanced cybersecurity solutions, ensuring your industrial infrastructure remains secure in the face of potential cyber threats.