They call it a "lock and key". Totally uncrackable over the internet or via USB, and although exploits do exist, for higher quality setups they take considerable time with physical access to the device.
The "IoT" is not our friend, folks - It turns solid, reliable old-school products into yet another vector for malware in your house. And if you think reinstalling Windows sucks, how about having your oven go into self-cleaning mode during your vacation without the safety latch closed? How about having your blender "playfully" get your cat's attention with brief pulses before going full puree? How about overriding your on-demand hot water heater to its "steam clean" setting with you in the shower?
I love toys, including electronics. But the fewer things in my house vulnerable to remote exploits, the better. My toaster should have one dial and one lever and zero computers, period.