In an era where innovation often outpaces implementation, legacy systems remain a hidden yet significant threat to cybersecurity. A recent breach involving DemandScience, a business-to-business data aggregator, highlights the risks that outdated and neglected systems pose. The incident, which exposed sensitive data linked to over 122 million individuals, was traced back to a system that was declared as decommissioned for approximately two years. Unbeknownst to the company, this retired system remained exposed, exemplifying a pervasive issue in IT: the failure to secure and monitor legacy assets.
This massive data breach underscores the importance of proper awareness and management for all outdated hardware, software and processes that an organization continues to rely on or even retains without actively using. The security risks associated with these legacy systems can lead to severe consequences, including steep financial costs and lasting reputational damage. Addressing this challenge requires careful inventory processes, proactive strategies to reduce vulnerabilities and ongoing monitoring of the IT ecosystem.
Why Legacy Systems Pose Security Risks
Legacy systems come with significant drawbacks. Many of these systems no longer receive vendor support or security updates, leaving them vulnerable to exploitation. In addition, they often lack compatibility with modern security tools, complicating efforts to monitor and protect them effectively.
An additional challenge arises from undocumented or “inherited” systems that fall outside the scope of regular IT audits. These systems, which often result from mergers, acquisitions and shadow IT, create gaps in visibility and increase risks. For attackers, these hidden vulnerabilities are attractive targets because they offer an easy way to infiltrate networks or access sensitive data.
Strategies for Addressing the Risks of Legacy Systems
The best way to mitigate the risk of legacy systems is to remove them. However, this is not always practical; legacy systems often need to remain in operation for valid reasons, such as their role in supporting critical business processes, maintaining compliance with regulations or managing historical data.
When legacy systems cannot be retired, organizations can mitigate the security risks associated with them while ensuring they continue to support business needs. Critical best practices include the following:
- Collect and maintain an up-to-date inventory of all hardware, software and processes using a tool like a configuration management database (CMDB). This strategy helps ensure that no system is overlooked and security measures are comprehensive.
- Conduct regular security assessments across all connected devices, including vulnerability scans and penetration tests, to uncover and address weaknesses before attackers can exploit them.
- Isolate legacy systems using network segmentation to minimize the potential damage of an attack and prevent outdated systems from serving as an entry point to the broader network.
- Implement strong access controls with tools such as identity and access management (IAM) systems and multifactor authentication (MFA). Regularly review access permissions to ensure only authorized individuals can interact with sensitive systems.
- Monitor for unusual activity across the IT ecosystem, including suspicious access to legacy data and use of older systems. Ideally, use an IT auditing solution that provides detailed alerts to appropriate teams in real time and offers functionality to facilitate incident investigation and response.
- Develop a clear asset retirement plan that includes securely decommissioning systems no longer in use and transitioning dependencies to modern platforms.
Securing the Future
More broadly, addressing the challenges posed by legacy systems requires adopting a lifecycle approach to IT management. Critical steps include planning for end-of-life transitions and leveraging automation tools to monitor and secure systems.
To ensure that IT environments evolve alongside business needs, organizations must also invest in modernizing their processes. For example, it’s essential to train IT teams on risk mitigation strategies that reflect a deep understanding of emerging cyberattack tactics and techniques.
DemandScience Breach: A Wake-Up Call
The recent DemandScience breach serves as a stark reminder of the dangers posed by legacy systems. A long-decommissioned system remained exposed, ultimately resulting in the compromise of millions of sensitive records. Organizations should treat this incident as a wake-up call to reevaluate their legacy IT management strategies. Legacy systems require deep visibility, proactive protection measures and ongoing vigilance.
The lesson from the DemandScience breach is clear: Legacy systems are not just relics of the past — they are active risks in the present. By prioritizing security and modernizing outdated assets, organizations can protect themselves from similar threats and build a safer, more resilient IT ecosystem.
