Coldcard-Related Bitcoin Sweeps Total Estimated $88 Million

A suspected third wave of Coldcard-related bitcoin sweeps has pushed the observed incident to an estimated $88 million in stolen assets. The three waves drained about 4,585 addresses and captured bitcoin worth approximately $88.6 million at the time of analysis.

The first wave was the largest, sweeping 1,082.65 BTC from 1,195 addresses in 41 minutes on July 30. A second operation collected 76.16 BTC from 1,478 addresses the following day.

Galaxy Research connected the activity to a vulnerable Coinkite Coldcard firmware release shipped on March 17, 2021. None of the affected coins were created before that release, and the median victim address had remained inactive for about 3.5 years, matching the behavior expected from long-term cold storage.

Centralized cryptocurrency exchanges recorded a sharp increase in bitcoin deposits on July 31, with a net inflow of 11,163 BTC during the day. This spike in deposits often attracts attention because coins deposited at trading platforms may be prepared for sale, collateral, or internal custody transfers.