[blinky1456]

Requiring physical access to the keyboard by the attacker first, makes this less impactful.

With physical access the they keyboard/computer, they could plant any other number of devices/bugs or extract information.

[molticrystal]

Once you are at physical access, you can go to town. Optical surveillance and even recording the sound of the keys being stroked to calibrate[0] an acoustic cryptoanalysis algorithm.[1]

[0] https://www.schneier.com/blog/archives/2005/09/snooping_on_t... [new algorithms require less time]

[1]https://en.wikipedia.org/wiki/Acoustic_cryptanalysis

[DEADBEEFC0FFEE]

Physical access road wireless keyboard, even if the system is physically secured is different. Typing some characters and recording the traffic, on a logged out computer, that totally possible and a lot less suspicious.