No need to go into the back story on this.  If you are reading this, there is a chance you’ve already read other reports on what Meltdown / Spectre and the perceived risks.

Cononical made a public statement last week to provide a patch for supported Ubuntu releases against Meltdown and Spectre security vulnerabilities, and the first set of patches are now available in the stable software repositories of Ubuntu 17.10, Ubuntu 16.04 LTS, and Ubuntu 14.04 LTS.

ref: https://insights.ubuntu.com/2018/01/04/ubuntu-updates-for-the-meltdown-spectre-vulnerabilities/

For Ubuntu 17.10 (Artful Aardvark), the updated kernel also patches four other security issues related to the Berkeley Packet Filter (BPF) implementation in the Linux kernel, which could allow a local attacker to execute arbitrary code or crash the system by causing a denial of service (CVE-2017-17863, CVE-2017-16995, CVE-2017-17862, and CVE-2017-17864).