Application Retirement Is Now Mandatory
By Emanuel Böminghaus, Legacy Systems Expert and Managing Director, AvenDATA
By Emanuel Böminghaus
Legacy Systems Expert and
Managing Director, AvenDATA
Managing Director, AvenDATA
AI Is Fundamentally Changing the Threat Landscape for Legacy Systems
For a long time, application retirement was primarily a matter of cost optimization and infrastructure modernization. That view is now outdated. Modern AI models have reached capabilities that were unthinkable just a few years ago. They analyze source code, probe applications for weaknesses, and detect security gaps at a speed human teams can barely match. This is especially problematic for companies that still run outdated legacy systems. Many of these applications were built long before cloud environments and AI-driven security analysis existed, when the threat landscape looked very different. What looks like a harmless legacy system today can become the entry point for an attack tomorrow. As a result, application retirement is becoming a core security measure. The question is no longer whether vulnerabilities will be found, but how quickly modern AI systems can identify them.
Why Legacy Systems Are Becoming Easy Prey for AI
Many legacy systems run on outdated technology, no longer receive security updates, and are often understood by only a handful of specialists. These are exactly the systems that AI-driven security analysis increasingly exposes. When Anthropic previewed its frontier model Claude Mythos in April 2026, the company reported that it had found thousands of high-severity vulnerabilities in every major operating system and web browser within a few weeks. Anthropic initially limited access to a small group of vetted partners through its Project Glasswing initiative instead of releasing the model publicly.
For businesses, this marks a new reality. Vulnerabilities that went undetected for years can now be found in a fraction of the time. At the same time, the barriers to entry for attackers are falling: what once required highly specialized expertise is increasingly being automated. Every legacy system left in operation expands the company’s potential attack surface. We take a closer look at this risk in Legacy Systems Are Becoming a Security Risk: Why AI Raises the Pressure to Act.
Application Retirement as an Active Security Strategy
Against this backdrop, application retirement becomes an effective way to reduce risk. A system that has been shut down can no longer be attacked. Companies should review which applications are still genuinely needed in production and which are kept running only to provide access to historical data. ERP systems, HR solutions, document management systems, and custom in-house applications often stay live for one reason alone: users still need to access legacy information.
The safer alternative is to archive the data in an audit-proof format and decommission the original systems entirely. This removes potential vulnerabilities, open interfaces, outdated user accounts, and unsupported software components from the IT landscape, while all relevant information remains accessible. For SAP environments, see how ViewBox compares with SAP ILM for system decommissioning. Application retirement reduces not only costs but, above all, the risk of future cyberattacks.
The Greatest Danger Isn't AI. It's Old Systems
The debate around AI often centers on the risks of the technology itself. For many companies, though, the real danger lies elsewhere. Modern AI exposes what is already there: weaknesses, misconfigurations, and security gaps that have gone unnoticed for years. Initiatives such as Anthropic’s Project Glasswing, which gives vetted organizations access to advanced AI models for defensive vulnerability research, show how seriously the industry now takes this shift.
For CIOs and IT leaders, the conclusion is clear. Anyone who keeps running legacy systems has to assume that their vulnerabilities will be found far faster than before. Application retirement is no longer merely an infrastructure project. It is an investment in cybersecurity, in a smaller attack surface, and in the long-term viability of the business.
AvenDATA helps companies decommission legacy systems securely and in an audit-proof manner. By archiving historical data, companies can shut down legacy systems completely and eliminate potential points of attack for good. See how 63 companies retired their legacy systems with AvenDATA. Reduce your attack surface, strengthen your security, and lay the foundation for a modern IT landscape. Contact AvenDATA to learn how application retirement can deliver a lasting reduction in your cyber risk.