Talking about JVNs. As far as I know, the in-english games aren't being treated this way, but then, I either buy or don't bother with English versions, so it isn't relevant to me.
Not all cracks are infected, but the percentage is high enough that isn't worth the risk to use them, even if you just want to unlock a game that runs too heavily because of the drm (another issue softdenchi causes, as I once saw it using half a gig of RAM). I had to reformat one of my PCs after cracking a few games I bought off of DMM three years ago, because the bitcoin miners included in the package were occupying most of my RAM and my graphics card's capacity.