Karpelès Develops Tool to Scan Closed Hardware Wallets for Hidden LTE Antennas

Former Mt. Gox CEO Mark Karpelès is developing a low-cost device to scan closed hardware wallets for hidden LTE antennas associated with supply-chain attacks, without opening them.

The concept would send a faint radio signal and measure the wallet’s resonant frequency to flag a possible antenna. The check is designed to detect the hardware while the wallet remains closed.

Karpelès previously described finding a Ledger device with a module wired to the screen’s data line, LTE/eSIM hardware and an antenna. The setup may have captured recovery words displayed on the screen and sent them over cellular networks, as detailed in an earlier examination of a tampered Ledger device. He also published a catalog of 14 Ledger devices classified as tampered or counterfeit, including modified units with added circuitry.

The project is still at the concept stage. Karpelès plans to publish the circuit-board design and specifications so others can build the device, with a prototype expected in the coming weeks.