Coldcard Users Hit by Fresh Wave of Coordinated Theft

Coldcard users are being targeted by yet another wave of coordinated thefts. According to research from Galaxy, this new wave has already swept around 389 Bitcoin (BTC) in a matter of hours.

The activity was flagged by Galaxy's research head Alex Thorn on Monday, who noted that the transactions averaged 13.8 sweeps per block, roughly 45 times the rate observed in a pre-incident control window.

This follows the disclosure of a previously undetected Coldcard firmware flaw that has caused affected devices to generate wallet seeds with less entropy than intended. The latest estimates suggest that thousands of wallets have been impacted, with over $90 million in Bitcoin stolen so far.

Affected users who control the relevant keys may be able to broadcast a conflicting transaction with a higher fee to move their funds to a secure wallet before the attacker's transaction is confirmed.