Binance founder CZ advises wallet diversification after $70 million Coldcard exploit

A significant exploit targeting Coldcard hardware wallets has resulted in the loss of nearly $89 million in bitcoin due to a vulnerability in a March 2021 firmware release. Attackers exploited a flaw related to weak software-based randomness used in key generation, enabling them to reproduce private keys and systematically drain bitcoin from affected wallets. This attack has impacted 4,585 addresses, with a total of 1,367 bitcoin stolen across three waves of attacks. The incident has prompted Binance founder Changpeng Zhao (CZ) to advise cryptocurrency holders to diversify their assets across multiple wallets. This event highlights the inherent risks associated with even established self-custody solutions within the cryptocurrency space. The exploit specifically targeted keys generated using compromised randomness, allowing attackers to gain unauthorized access to the bitcoin held within these wallets. The scale of the loss, amounting to approximately $89 million, underscores the potential financial ramifications of such security breaches. The advice from CZ emphasizes a proactive approach to risk management for crypto investors, suggesting that relying on a single hardware wallet may not be sufficient to protect against sophisticated exploits.