my homeserver is compromised and has beenpart of a bitcoin mining farm for years
The very first Linux server I deployed on a VPS was hacked almost immediately because of my ignorance. The bot gained entrance, and they supplanted a miner rig. Now, on a tiny VPS, it's pretty easy to tell if you're running a coin miner because all of the resources will be pegged. However, I got to thinking, on a corporate server, if they did manage to do this, it would almost be undetectable until someone started reviewing logs.