What ever happened with the mysterious issue of wallets draining randomly not to long ago?

Do you guys remember a couple of moths back that some people's wallets were being drained and no one at the time seemed to know how they got compromised. I'm not talking about the usual "I was hacked and got drained and all I did was share my private key with someone from India claiming to be my Nigerian Prince missing brother."

I'm talking about wallets that were dormant for a while and then suddenly got drained. I bring this up in light of the Mark Cuban fiasco that befell him recently and am curious if this had anything to do with it.