Binance founder Changpeng “CZ” Zhao has urged cryptocurrency users to reconsider their trust in hardware wallets following a significant Bitcoin theft linked to Coldcard devices. The incident, which saw over 1,082.65 BTC ($70.2 million) stolen from 1,196 addresses in a 41-minute window on July 30, exploited a firmware vulnerability dated to March 2021.
The flaw, identified by engineers at Block, allowed private keys to be guessed more easily, compromising funds stored on affected devices. Coinkite, the manufacturer of Coldcard wallets, issued emergency hotfixes to mitigate further risks. However, updates do not address seeds already generated on compromised devices, leaving some users vulnerable.
Zhao’s warning comes as Galaxy Research traced the stolen Bitcoin to a small number of addresses, which have remained unmoved since the theft. He emphasised that no security measure is foolproof, stating: “Nothing is 100%.” The exact number of affected users and the full extent of the breach remain unclear, with investigations ongoing.
Written by Daniel Brooks
Security Desk
