Man, I wish there were some pictures. I didn’t even know that there are LTE modems that small.
Apparently the hacker did remove the battery and replace it with a smaller one, leaving enough room for the tiny eSIM/LTE modem / OCR chip that did recognition of the secret on screen.
They're here. It's wild.
I guess the sweatshop workers would then need to be trained in reballing BGAs if they did that.
Give me a shitty html4 page with the text ffs.
tl;dr Implant is just a little cell phone that does OCR of the hardware wallet's screen during setup to steal the recovery phrases. The implant's design has improved notably three different times before landing on a pretty darn sleek spot-welded overlay that is laminated flat onto the host.
This was already the level of integration 13 years ago: https://www.bunniestudios.com/blog/the-12-gongkai-phone/
Observe how the SIM card socket is the biggest part on the board: http://bunniefoo.com/ntw/dozendp_8.png