Securing the Past for the Future OPC DA and DCOM

In the evolving landscape of industrial automation, legacy systems continue to play a pivotal role. These systems, designed to live for 15 to 20 years in an era when cybersecurity was not a top concern, now exist in a world where digital threats are both sophisticated and relentless. Among these legacy technologies, OPC DA stands out. It's a protocol that revolutionized data exchange in industrial environments but, in its reliance on DCOM for the communication between the software components of Networked devices.

Why focus on DCOM and OPC DA? Because understanding this intersection of legacy technology and modern cybersecurity threats is crucial for protecting critical infrastructure.

Over the years, various vulnerabilities in DCOM's RPC implementation have been identified, many of which allowed for remote code execution, denial of service attacks, or privilege escalation, that had a direct impact on the security posture of the OT systems.

In 2023, many users still neglect basic security measures like patching or even reviewing the basic hardening settings of DCOM on a regular basis. This negligence exposes systems to potential operational disruptions, system downtimes, or even catastrophic failures in critical processes, especially in DCS, ESD, and F&G systems.

The implementation of classical basic controls for systems reliant on DCOM and OPC DA, such as regular patching, strict access controls, and network segmentation, remains effective in mitigating the risk of exploitation. Continuous monitoring, utilizing anomaly detection solutions, will help to enhance the overall security posture of these legacy systems. Where possible, considering migration to more secure, modern solutions such as OPC UA is also advisable.

In summary, it is call to action for cybersecurity experts and end-users alike. It's not enough to keep these systems running merely because they still function.A passive approach to legacy system security is no longer tenable. Instead, there's a pressing need for a proactive reassessment and continuous enhancement of the cybersecurity posture of these systems. This involves not just adhering to foundational security practices but also actively seeking out and implementing improvements