CZ Advocates for Wallet Diversification After Coldcard Breach

Following a severe $70 million security breach impacting Coldcard wallets, Binance CEO Changpeng Zhao, widely known as CZ, is advising crypto holders to diversify their assets across multiple wallets. This advice comes in the wake of significant unauthorized transactions detected by users of Coldcard devices.

Zhao's recommendations were made public on Saturday, emphasizing that even hardware wallets are not immune to vulnerabilities. He noted, "Even hardware wallets can have bugs... Nothing is 100%. Stay informed. Stay SAFU!" His comments reflect a cautious approach to managing cryptocurrency holdings.

The breach, which began on July 30, was traced back to a firmware flaw introduced in March 2021. This flaw affected the generation of recovery seeds for certain Coldcard models, allowing attackers to reconstruct private keys offline and access funds without physical devices. Initial estimates suggested that about 594 BTC, valued at $38 million, was stolen within a short span. However, further investigation revealed that the actual amount was around 1,082.65 BTC, or approximately $70 million, taken from 1,196 wallets.

Coinkite, the producer of Coldcard, has acknowledged the issue, offered apologies, and released critical firmware updates. Users have been urged to generate new seeds on updated devices, as simply applying firmware updates does not protect previously created seeds that were compromised.

This incident has reignited concerns regarding self-custody and the inherent risks involved. Although hardware wallets are often deemed secure for offline Bitcoin storage, the Coldcard breach illustrates that vulnerabilities can persist in even the most trusted of devices. Zhao's call for diversification underscores the necessity for users to be proactive in managing their crypto assets.