I would love to see a source of a large company like CNN knowingly serving malware in the guise of ads. I've never heard of that but I'm all ears; I feel like it would be big news if CNN knowingly put a crypto miner on your device.
> How should I legally/ethically block this malware without using a broad ad blocker?
I don't know but also now you're committing a fallacy known as "Irrelevant conclusion". Yes, there's a genuine question on how you can block malware without depriving website owners of their ad revenue, however it's irrelevant to the original argument of whether blocking ads is stealing (which we've somehow come to from a piracy argument but whatever). The argument becomes "Is blocking ads stealing when some of them give me malware", but that's separate from "Is blocking ads stealing".
Alternatively you might be trying to argue "but I block ads because some of them give me malware" which can be an appeal to pity[2], but I don't think you're trying to go that far.
[1]https://en.wikipedia.org/wiki/Irrelevant_conclusion [2]https://en.wikipedia.org/wiki/Appeal_to_pity