If you make or use software at work, knowing where all your tools are in their lifecycle is vital. Long-Term Support (LTS), Security Phase and End of Life (EOL) are some crucial terms you'll hear.

* Long-Term Support (LTS)

* Security Phase

* End of Life (EOL)

Long Term Support means you’re probably on the latest or a recent version. You still get updates, customer support, bug fixes, and new features.  

Once newer versions are released, previous versions often go into a Security Phase if there are still many users unable to upgrade immediately. A product in its Security Phase will receive security updates only, and users are encouraged to update to a newer version before a specific date, where the product enters End of Life.

End of Life means the software publishers no longer work on that version at all. No security updates, and likely no help if something goes wrong.  

That means that if a security vulnerability like the one Umbraco issued in July 2023 is discovered in an unsupported legacy Umbraco version, your site will be vulnerable (and likely immediately targeted, if the vulnerability can be detected by malicious crawlers)

In the early days of software, staying on a preferred older version sometimes provided stability and compatibility. Today it mostly means security nightmares, mountains of tech debt, and frustrated employees.  

Have a look at Umbraco’s detailed guide to the LTS, Security and EOL phases for all of its current versions:

Umbraco Long-term Support (LTS) and End-of-Life (EOL)

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