There are emails and social media messages going around from “authorities”. They claim to have the latest updates to solve the Spectre and Meltdown issues. So far they have been seen in Germany, UK, and France.
They are fake! The link is leading you to malicious sites. Just delete them.
Turn on “Automatic Updates” on your system. And yes, Apple has the same problem. Not so sure about ARM, mostly used in phones and tablets.
Oh, and btw: Happy New Year!