Trezor Confirms Hidden Implants in Safe 5 Wallets Sold by CryptoBilis

Trezor said that three Safe 5 wallets bought from the reseller CryptoBilis contain an extra circuit board, or implant, that can copy their recovery phrases. The implant reads the phrase from the screen and sends it over the mobile network to a server controlled by the attackers. Trezor examined one wallet in its lab, identified the other two from photos sent by their owners, and has had no reports of lost funds.

A firmware update, version 2.13.1, stops the implants found so far from capturing anything on wallets that run it, the company said, but the update cannot protect a wallet backup captured before it. Trezor still advises anyone who bought a Trezor from CryptoBilis since March to move funds to a new wallet with a new recovery phrase, and to contact Trezor Support, which offers a new wallet to those buyers. The company said it will not publish technical details that could help attackers.

CryptoBilis was an official Trezor reseller in Southeast Asia until October 9, when Trezor removed it. Ledger had begun investigating losses of funds among the reseller's customers on the same day and later confirmed an unauthorized implant in a wallet the reseller sold. Trezor says its implants work the same way, and it has not said who fitted them or where in the supply chain that happened. Trezor has also cut its reseller network by about 80%.

Why it matters For security leaders and investigators, this case shows that hardware wallets can be compromised before delivery, so a device's integrity depends on its supply chain as well as its firmware. A firmware update does not undo a recovery phrase already captured, so organizations and individuals holding funds on affected devices should treat the phrase as exposed and move assets to a new wallet with a new phrase. Trezor's account also leaves open who fitted the implants and where, which investigators should weigh when assessing other resold devices.