In the world of OT, ensuring the security and reliability of systems is critical. Disruptions to critical processes can have severe consequences, impacting production, safety, and even environmental well-being. The focus on uptime may sometimes conflict with another essential aspect of OT security, patch management.

Applying security patches regularly is essential for mitigating security risks. On the surface, this seems to be straightforward: simply apply software updates to your OT systems. However, patching in OT environments poses unique challenges. 

Challenges of OT Patch Management

  1. Lack of Visibility and Control: OT networks are frequently isolated from IT networks, and there is little control and visibility over devices that require patching. Automatic inventory and monitoring of OT systems can be challenging with traditional tools, making it difficult to determine which systems require updates and to deploy patches.
  2. Downtime Constraints: OT systems often operate 24/7. Any downtime can lead to production delays and lost revenue, even for maintenance or patching. This makes it difficult to schedule patches and updates without disrupting operations.
  3. Compatibility Issues: OT environments typically consist of a mix of legacy and modern systems, often running specialized software and hardware that may not be compatible with the latest security patches. Introducing new patches can lead to compatibility issues with existing resources.
  4. Limited Resources: OT security teams are often stretched thin, making patch testing and deployment challenging, and due to the continuous operation of OT systems, the windows available for applying patches are often limited. These windows must be planned to minimize impact on operations, which could cause the deployment of security updates to be delayed.
  5. Legacy Systems: Many OT environments rely on outdated infrastructure that may not receive vendor security updates or continuous support.

Best Practices for OT Patch Management

  1. OT Asset Inventory and Asset Criticality: An up-to-date OT asset inventory, including hardware, software, and firmware versions, is the foundation of effective patch management. This inventory is crucial for identifying which systems need patches, assessing the potential impact of updates, and prioritizing patching based on the risks they pose.
  2. Vendor Coordination: Stay informed about the latest patches and updates. Establishing strong relationships with vendors can help ensure timely access to critical patches and support for compatibility testing.
  3. Test and Deploy Patches: Thorough patch testing is crucial to ensure compatibility, stability, and functionality. Since patching isn’t as simple as applying it whenever needed, it must be coordinated with downtime schedules. Many patches require a reboot on systems that may not have been rebooted in years. Determine how much time is required and where that window of time will fit in the overall downtime schedule.
  4. Create a Patch Management Process: A comprehensive patch management policy should outline roles, responsibilities, and procedures for patching OT systems, including evaluating, testing, and deploying patches. This policy should be aligned with organizational goals and compliance requirements.
  5. Monitor and Review: Monitor the effectiveness of your patch management process and review it regularly. Use metrics such as patch deployment times, system downtime, and incident rates to identify areas for improvement.

OT Patch Management Using Cyber Insights and Cyber Watch

Cyber Insights is designed to help industrial organizations gain much-needed operational visibility into their OT cybersecurity posture. This includes automated asset discovery and advanced monitoring without disrupting operations, helping organizations overcome the lack of visibility and control, one of the key issues in OT patch management. 

Another challenge in patching is compatibility, specifically matching between assets and the updates they require. Collecting a list of available patches is simple but matching them to the correct assets in the OT network can be a time-consuming nightmare. Cyber Insights identifies vulnerable assets in the network and helps determine which patches apply to which systems.

Cyber Watch is designed to provide a centralized view into multiple sites’ cybersecurity posture, which helps identify, prioritize, and respond to incidents.