The same way you can't be sure that when you drive to work today you are not going to die, you can't be sure that your machine isn't compromised somewhere. That

The same way you can't be sure that when you drive to work today you are not going to die, you can't be sure that your machine isn't compromised somewhere. That's just how reality is: safety is an illusion. Like with driving, make an effort to lower the probability to wherever makes you comfortable, then just accept that there's a non-zero chance it wasn't good enough.