I think we may have forgotten the biggest contributor, besides phishing email in the spread of malware/ransomware in recent years, not just Kupidon - "Downloading torrent files". There are literally millions being downloaded everyday, and majority of those files have some have malicious intent. That's why people should stay away from it, specially crypto enthusiast as you might one day be affected by ransomwares.
According to the article of bleepingcomputer it's origin are still unknown and their biggest guess is that it is coming from remote desktop servers, so there are no downloads required or emails needed to be click in order to get the malware. The hacker just need to access your pc with this remote servers in order to infiltrate your computer with the malware. Like I said this kind of ransomware is unique since it doesn't require the user to have any kind of error in his side like visiting websites, clicking emails, or even downloading torrent files.
It doesn't come from remote desktop servers, it infect your exposed remote desktop servers, which is not the same.
It does require a vulnerability in a remote desktop server application installed on your computer, so it also require you to have a port opened (+ a vulnerability). Otherwise a download is required to get this malware on your computer. A download and an execution (and since you can download and execute files though a remote desktop application then if there is a vulnerability in your application someone can take an advantage of it)
Malwares that require you to visit a website to be infected (by using a Remote code execution vulnerability) are far more dangerous than this kind of old stuff. This malware is new but what he does is not, and not as sophisticated as a remote code execution vulnerability in your web browser (which can be used to infect millions of people even if they don't have any port opened).
You can sleep peacefully if you don't have a remote desktop server with your bitcoin on it
I have Windows based machine, but recently though, I try and exploit Unix flavor for safety purposes. Just a couple of days ago, was able to create a Linux Mint system. Still playing with it and probably will move out from Windows based OS specially if I deal with my crypto.
You are not protected under Linux if you don't know how to protect yourself using it.
People think that there is no malware under linux but they are wrong, most of the malwares are made for windows because there are more windows users. If you don't want to learn a bit of security then whatever if you use linux or mac or windows you must be careful of what you download over internet.