Legacy Systems Are Becoming a Security Risk: Why AI Is Dramatically Raising the Pressure to Act

By Emanuel Böminghaus, Legacy Systems Expert and Managing Director, AvenDATA

By Emanuel Böminghaus

Legacy Systems Expert and
Managing Director, AvenDATA

Legacy Systems Meet a New Generation of Cyberattacks

Legacy systems are older applications and IT platforms that companies continue to run even though their underlying technology is outdated or they’re barely needed operationally anymore. These systems often stay active for one simple reason: historical data, records, and business transactions still need to remain accessible. But with the rise of powerful AI models, the risk landscape is changing. Attackers can now analyze vulnerabilities faster, automate attack patterns, and process large volumes of technical information far more efficiently. At the same time, many companies have spent years building complex IT landscapes with numerous interfaces, old user accounts, and poorly documented dependencies. This creates a structural problem for CIOs and IT leaders.
Play Video
Every unnecessarily maintained system potentially expands the attack surface. Companies should therefore systematically review which legacy systems are actually still needed for production use and which ones can be permanently decommissioned through secure archiving.

Why Legacy Systems Are Increasingly Becoming a Cyber Risk

Old applications don’t just drive up maintenance and licensing costs—they can also create significant security risks. Vendors stop issuing updates, operating systems reach end-of-support, and specialized expertise disappears along with departing employees or service providers. Meanwhile, outdated authentication methods, inadequately protected interfaces, and permission structures that have grown organically over time often remain in place. Modern AI tools are making this situation worse, since cyberattacks themselves are becoming increasingly automated and scalable. A forgotten system can end up becoming an unnecessary gateway into a company’s infrastructure. On top of that come compliance risks and operational dependencies. Companies looking to retire legacy systems shouldn’t focus solely on direct operating costs. What matters is the full risk picture spanning cybersecurity, compliance, staffing effort, and business continuity. The larger and older the application landscape, the more important a structured decommissioning process becomes.

Decommission Legacy Systems Safely—Without Losing Data

The challenge lies in shutting down legacy systems without losing the company data that’s still needed. This is exactly where professional, audit-compliant data archiving comes in. Data and documents are extracted from the original system and kept available long-term on an independent archiving platform. This process must take statutory retention periods and requirements into account. At the same time, business units, internal audit, and external auditors still need traceable access to relevant historical information. Companies should therefore avoid simply copying databases or permanently virtualizing entire legacy applications. The goal must be to archive legacy IT data, preserve its business context, and eliminate technical dependency on the original system. Only once data access, permissions, traceability, and legal requirements are fully assured can the production infrastructure be shut down in a controlled and permanent way.

Less Attack Surface, Lower Costs, and Stronger Compliance

Consistently decommissioning legacy systems that are no longer needed reduces the complexity of the IT landscape. Servers, databases, interfaces, and old operating systems no longer need to be operated, monitored, patched, or maintained by specialists. This can reduce infrastructure, licensing, and staffing costs while simultaneously shrinking the potential attack surface. Especially as AI models continue to grow more powerful, reducing unnecessary systems is becoming an essential part of modern cybersecurity strategy.
With AvenDATA, companies can extract historical data and documents from legacy systems, keep them available long-term, and then decommission the original applications in a controlled way. This makes it possible to combine cost reduction, compliance assurance, and cybersecurity in a single approach.
Work with AvenDATA now to review which legacy systems in your IT landscape are genuinely still needed—and which ones you can archive in an audit-compliant way and retire with confidence. Contact AvenDATA for an initial assessment of your legacy landscape.