Ubuntu 14.04 LTS, which is the basis for many cloud and enterprise services, is coming up on its end of life this April. Canonical will begin offering an Extended Security Maintenance service in April that will continue rolling out security patches. However, the service is designed primarily for enterprise customers.
https://www.notebookcheck.net/Canonical-extends-security-support-for-Ubuntu-14-04-LTS.333434.0.html