If only I knew how to create my own firmware for Leica... then I could call the same crypto-chip and sign any picture I'd like. (Oh wait! There's a github for hacking Leica M8 firmware!)
If I download a file from a questionable source: scan it (with clamscan)
If I run an executable I don't trust: use a locked-down (with firejail)
No matter the antivirus, if you keep downloading and running questionable files, you run the risk of viruses. I would say that browsing patterns are more important than any antivirus.
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