I aways wondered if the communication channel between my wireless keyboard and the usb receiver-antena is secure. I never bother to reseach this. Today I figured out the practical way. I turned on my pc at work and I tried to type the first letter of my password. Nothing hapened. Then I started spamming that letter. Still nothing, until the person next to me said “my keyboard is typing all by itself”. It turns out she has a wireless mouse with a seemigly identical receiver-antena usb.
The moral of the story. If it was so easy to almost leak my password unintentionally due to this flaw of wireless keyboard communication, imagine wad a bad actor can do intentionally. Why try to brute force, social engineer e.t.c. when your password can be stollen in transit from your keyboard to your pc.
My Wireless keyboard is a Keychron. It doesn’t have a dedicated adapter, it’ll connect to any device with Bluetooth capabilities. From what I’ve seen of how it works, is that it can store up to 3 device signatures to automatically connect to (you can choose which of the three is active). What I assume it’s storing is the MAC address which I thought is unique to the device.