@Michael Loucks
For the scenario you described to happen, it would require that the system firmware be compromised. That's orders of magnitude more difficult than compromising the operating system.
Exactly, so today's hackers are orders of magnitude more advanced than the neighborhood kid seeing what he can get away with in his basement.
Again, my recent hack was a less than one-year old 2018 Mac Mini, which was regularly updated to keep the clearly identified vulnerabilities patched. So again, there is no longer any such thing as a 'secure' system, only more secure than most computers.
I've currently had three 'secure' Apple devices compromised, an older iPhone I no longer used and a newer iPad I'd already replaced, and the more recent less than 1-year-old Mac Mini T2 chip (which couldn't keep the hackers out of the root firmware code. If the code in the root firmware was at least detectable, I'd know how to respond and at least prevent it from operating/communicating, but some infections are simply too friggin' advanced, even for us supposed experts.
That most recent infection is the one that's really put me into 'high-alert' mode against any more system compromises, since these guys have been targeting me for some time, but they rarely succeeded, until now (and no, the infection was not the very public EvilQuest or ThiefQuest Mac hacks, as those were the first things I checked for.
A good setup is to have a firewall device (like this: SG1100) inline between your router and your WiFi device. Breaching that kind of network security, as well as the local security on the Mac, is tough even for state-level actors.
Yeah, that's the one thing I haven't installed that I really need too, but the VPN options for Macs are generally pretty limited, given the OS's restrictions on what they can control. And the vast majority of anti-malware apps only flag the particularly notorious websites, but won't perform any 'deep dive' security sweeps (I use CleanMyMac X, which regularly updates and performs thorough checks, but it didn't register either the key logger nor the compromised firmware).
Again, the way they initially gained access was through my NetGear router, which are fairly easily hacked to reveal ALL the connecting devices passwords, so yeah, and hardware middleman would be an important protection. Thanks for the suggestion!