Ubuntu announced its 15.04 (Vivid Vervet) release almost 9 months ago, on April 23, 2015. As a non-LTS release, 15.04 has a 9-month month support cycle and, as such, the support period is now nearing its end and Ubuntu 15.04 will reach end of life on Thursday, February 4th. At that time, Ubuntu Security Notices will no longer include information or updated packages for Ubuntu 15.04.
The supported upgrade path from Ubuntu 15.04 is via Ubuntu 15.10. Instructions and caveats for the upgrade may be found at:
https://help.ubuntu.com/community/WilyUpgrades
Ubuntu 15.10 continues to be actively supported with security updates and select high-impact bug fixes. Announcements of security updates for Ubuntu releases are sent to the ubuntu-security-announce mailing list, information about which may be found at:
https://lists.ubuntu.com/mailman/listinfo/ubuntu-security-announce
Since its launch in October 2004 Ubuntu has become one of the most highly regarded Linux distributions with millions of users in homes, schools, businesses and governments around the world. Ubuntu is Open Source software, costs nothing to download, and users are free to customise or alter their software in order to meet their needs.
Originally posted to the ubuntu-announce mailing list on Thu Jan 14 00:37:14 UTC 2016 by Adam Conrad, on behalf of the Ubuntu Release Team