Coldcard Vulnerability Exposes Seeds, Draining 594 BTC From Wallets

A flaw in Coldcard devices reduced seed entropy, allowing attackers to guess keys and drain 594 BTC. Users must migrate funds as patches cannot fix compromised randomness.

Woofun AI reports that a security vulnerability in Coldcard hardware wallets allowed attackers to guess seed phrases previously considered secure. The flaw stemmed from predictable device information that narrowed the search space for wallet seeds, resulting in the drainage of approximately 594 BTC. Because software updates cannot rewrite the compromised randomness, affected owners are required to generate new seeds and transfer their funds to secure wallets.