Every piece of technology, whether it’s an operating system, firewall, or antivirus tool, has a life cycle. At some point, vendors stop updating or supporting their products. When that happens, those systems are considered end of life (EOL) or end of support (EOS). If they’re still active in your organization’s IT environment, they could be creating serious gaps in your cybersecurity strategy.
In this guide, we’ll walk through what EOL and EOS actually mean, how they differ, and why you should address them before they become major security liabilities.
End of life (EOL) refers to the point when a vendor stops developing or selling a product. While the software might still work at this stage, it won’t get any performance improvements, security updates, or new features.
You might have EOL systems that still run just fine (such as a legacy operating system, like Windows 7), but this doesn’t mean they’re safe or sustainable. Ivanti’s 2025 State of Cybersecurity Report found that 51% of organizations use software that has reached end of life, and 33% say legacy tech has seriously compromised their security.1
When software reaches EOL, it’s essentially frozen in time. It won’t keep up with evolving threats or work well with newer tools, and over time, it becomes more difficult to support.
While the terms EOL and EOS are often used interchangeably, there’s a big difference:
Some products reach EOS before they’re officially EOL, while others hit both at the same time. Either way, once support ends, the product is no longer reliable from a security or compliance perspective.
It’s easy to focus on whether something is still functioning, but when it comes to cybersecurity, the better question is whether it’s still protected.
Here’s how unsupported systems create risk:
Even if you’ve kept the rest of your security stack up to date, EOL and EOS systems open vulnerabilities into your network that hackers can easily exploit.
It’s not always obvious when a system has reached EOL or EOS, especially when nothing seems broken. Here are some signs to watch for:
The most obvious sign would be if your last support request was met with: “This product is no longer supported.” If any of these sound familiar, it’s a good idea to verify the product’s lifecycle status.
Addressing EOL and EOS risks doesn’t need to be complicated. Here are some steps your team can take to stay ahead:
Track all hardware and software in use, along with their version numbers and known lifecycle dates. This helps you spot potential risks before they become urgent.
Set calendar reminders or subscribe to product bulletins so you’re notified when support timelines change. Relying on expired contracts or third parties to alert you is risky.
Build EOL timelines into your IT planning and budgeting. Upgrading before support ends gives you more flexibility and helps avoid disruption.
A managed security services provider (MSSP) can identify outdated systems, recommend replacements, and manage upgrades on your behalf.
Over half (54%) of security leaders said unpatched vulnerabilities are their top concern in a 2024 survey.2 If you must continue using unsupported systems temporarily, make sure they’re fully patched (to the last available version) and isolated from the rest of your environment.
An EOL system doesn’t just affect its own security – it weakens your entire security posture. Even the best tools in your environment can’t compensate for a known vulnerability in an unsupported application or device.
For example, your firewall might be configured properly, but if an EOL operating system is running behind it with a known exploit, attackers may still find a way in. Your antivirus might be current, but if your core business platform can’t be patched, you’re still exposed. A legacy mail server or CRM could become a direct line into your network, even if your employees follow all recommended security practices.
In a modern security model, every part of your infrastructure needs to be accountable. Unsupported systems are a weak link that can put everything else at risk.
Some IT leaders put off replacing legacy systems to avoid upfront costs – but the hidden costs of sticking with EOL tools often outweigh the savings.
Planning ahead makes replacement smoother, more affordable, and less disruptive.
It’s easy to deprioritize EOL issues when systems appear to be working. But once something goes wrong, those legacy tools become barriers to recovery rather than business enablers. Addressing EOL and EOS head-on gives your team more control, more predictability, and more peace of mind.
At Aseva, we help businesses take a proactive approach to cybersecurity. Whether you're managing dozens of applications or just trying to secure a few critical systems, we’ll work with your team to build a clear, future-ready security plan.
Need help evaluating your current environment? Reach out to Aseva today and let’s make a plan that protects your business from EOL and EOS risks.
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