If you use a linux system, then you won't need karspersky at all.
If you use linux, you can install .deb software without being scared about viruses.
If you use a linux system, then you will be much more free of those companies based on scamming and pishing and you won't be afraid of malicious .exe anymore ...
But, of course, you will still need to be careful:
I always download the core to an off-line computer. I mean: I use even my ethernet, download the core, install my wallet and then this computer is going to be for this use only (I use an old notebook with fedora). I never download to this computer any software, I don't even watch an online movie in it. This is for one purpose only: safety.
Of course, I always print my wallet in a very well storage QR code, highly hidden (only my dog knows where it is, just in case...)
If I die, then my dog will be rich jajajaj