is theoretically possible to dump the keyboard firmware of a laptop, modify it and reflash it to make the keyboard works not properly ? I don't know even if the laptop keyboard has a firmware. Without accessing phisically to any chip. Just by software.
1 Answer
I'm not sure if laptop keyboards have firmware on their own, but keyboard input is usually processed by the embedded controller (EC), for example for handling hardware-related buttons such as brightness control. This firmware is often included as part of BIOS updates (and can be extracted from them).
For example, at Recon 2011 Alexandre Gazet presented a talk Sticky fingers & KBC Custom Shop which described analyzing a "keyboard controller" (but more likely EC) firmware to embed a backdoor code which would infect the host BIOS's SMM handler and (in theory) take over the machine on the lowest level. I was not able to find the English slides or video of the talk but there is a French paper from SSTIC 2011.
It in turn refers to the 27C3 (2010) talk The Hidden Nemesis: Backdooring Embedded Controllers by Ralf-Philipp Weinmann which instead the EC into a keylogger. Video of the talk is available.
answered Dec 23, 2021 at 23:41
