It depends on the malware. If it's self-contained and only goes around encrypting things and then prints a message to send money to a pre-defined particular Bit Coin address, then it won't matter.

If it needs to phone home or otherwise contact an outside address (excluding hard-coded IP addresses), then presumably it needs it needs to do a DNS look-up at some point.

Many botnets use pseudo-random DNS domains, and when the generation algorithm was figured out, people were able to get control of it:

* https://en.wikipedia.org/wiki/Botnet#Domains

* https://en.wikipedia.org/wiki/Fast_flux