Prevention Is the Only Cure: The Dangers of Legacy Systems

On Dec. 16, 2020, Accellion FTA, a 20-year-old file transfer appliance, became the subject of media attention by reporting a now-infamous zero-day exploit. Patches were quickly released later that month, with additional investigations leading to further patches over the next 60 days. Despite Accellion promoting awareness of the zero-day exploit, over 300 known victims have fallen to the vulnerability.

Conglomerates were no exception; energy giant Royal Dutch Shell is just one large-scale example. Despite advanced knowledge due to public cases in December and January, the oil and gas company found itself victimized by the third-party vulnerability and reported the breach on March 16, 2021, exactly three months after the first exploits. The oil giant became yet another victim of the same mistake: allowing legacy systems to take unmanageable root in the corporate IT infrastructure.

What Makes Legacy IT Risky?
What makes a system "legacy"? It's not simply the age of a machine or device but, rather, the machine's use and treatment — any system that becomes mismanaged or forgotten introduces complications, which run the risk of driving vulnerabilities to the larger IT environment. The crucial component of a legacy system is its introduction of an "inherited problem" where knowledge about systems is lost or documented "somewhere," outside the organization's usual channels and tools.

Even outside of IT, it is often easy to find examples of heavily used systems that are greatly outdated, undermanaged, or badly maintained. Whether it's a CT scanner used by dozens of doctors and nurses, or an old human-machine interface that has monitored turbine operations in the same power plant for years, it's all too common for organizations to rely upon a given tool or software with little knowledge of who is responsible for upkeep and maintenance.

Even when legacy tools are maintained operationally, in critical sectors like energy, healthcare, and transportation, the gap between operational technology (OT) maintenance and IT maintenance can drive exposure. Legacy systems are often maintained only to ensure function, and their operations are often digitized with upgraded Internet of Things (IoT) functionality for the sole purpose of operability. OT maintenance may fail to consider the IT and cybersecurity perspective, seeking to make changes to improve systems without questioning if those systems remain secure. While these legacy systems may seem helpful after years of use, networked systems' prolonged exposure to these legacy devices proves time and time again the familiar adage: What can go wrong will go wrong.

To determine if an aspect of your infrastructure is legacy, ask yourself:

Shadow IT Increases Legacy Technology Threats
As companies organize their first post-pandemic steps back into an office or hybrid workflow, the threat from legacy systems is greater than ever. In part, this is due to the legacy of shadow IT, in which systems or devices are introduced without explicit IT department approval. It is more than likely that the rapid shift to work from home caused an uptick in shadow IT, attack surfaces, and exposure to related vulnerabilities.

Large corporations like Shell have proven time and again that they are vulnerable to these attack vectors, but they may not need to be as concerned about shadow IT as their midsize counterparts. While large staff size may increase the potential for mismanagement, major corporations are also more likely to have systems and audits in place to manage their environment and control changes. Many midsize businesses and enterprises may be less aware of weaknesses in their system that leave them exposed to shadow IT's risks.

Minimizing Risks of Legacy and Shadow IT
How can a firm prevent the proliferation of legacy or shadow IT? The only solution is the proper management of all aspects of IT. Companies must plan as they scale, creating management hierarchies that ensure that one (or a few) crucial employee's absence or retirement will not open up a system to attack. Training IT staff to share and partition responsibility can help develop a healthy and agile management hierarchy, which includes responsibilities by non-IT departments for the systems they use. This enables IT teams to act proactively so that even if a vulnerable system cannot be patched or updated, compensating controls can be set in place.

To develop this responsive IT management hierarchy, IT administrators should turn to tools that enable them to understand all aspects of their environment and track and subsequently control any changes introduced to that system. Doing so is not only crucial to achieving and maintaining operational resilience, protecting the firm from hacking or even ransomware attack, it also prepares firms to grow and securely scale digitalization.