So far this year, Windows leads the scorecard regarding mass infections and business downtime due to them.
So while indeed, open source is not a guarantee for better security, the results are in its favor. It might also be because it's not such an attractive target to hackers due to its low share in the desktop market. But still there millions of linux servers online 24h/24h and I assume they have a bigger potential for monetisation.
Windows also leads the score card in installation base, which I think is the real causal relationship. If Linux was installed on 90% of desktops you better well believe there'd be a similar number of exploits for it. Something similar happened to Mac OSX not too long ago, as they grew in popularity more and more exploits were found for the operating system.
That's what I tried to express above. I was also wondering what is more profitable in the ransomware economy: infect many, almost worthless machines? Or infect an order or two of magnitude fewer machines, but with a higher chance of paying?
I'd say with a higher chance of paying because people administering them are more likely to know how to buy bitcoins, how to send them and what to do with the decryption key.
So while indeed, open source is not a guarantee for better security, the results are in its favor. It might also be because it's not such an attractive target to hackers due to its low share in the desktop market. But still there millions of linux servers online 24h/24h and I assume they have a bigger potential for monetisation.