Key facts
- Bitcoin transfers under 1 BTC hit their highest daily volume since the FTX exchange collapse.
- Approximately 39,600 BTC was moved in small transactions on Friday.
- The ongoing suspected Coldcard hack has resulted in estimated losses of 1,367 BTC ($88.6 million) across 4,585 addresses.
- A recent attack wave drained an additional 207.7 BTC.
- A new wave of attacks on Monday impacted 218 transactions and 462 addresses, moving approximately 388.9 Bitcoin.
Bitcoin users have moved the largest amount of BTC in small transactions since the collapse of FTX, with 39,600 BTC transferred on Friday. This surge in activity is linked to an ongoing suspected hack of Coldcard hardware wallets, which researchers warn remains active and could eventually drain all vulnerable devices.
Galaxy Research reported that the suspected Coldcard hack has led to an estimated loss of 1,367 BTC, valued at approximately $88.6 million, across 4,585 addresses. The firm's head of research, Alex Thorn, warned that the attack was still ongoing and urged users to move funds from Coldcard-generated addresses immediately. The flaw stems from a March 2021 firmware error that caused seed phrases to be generated with insufficient randomness, leaving private keys guessable. The stolen coins had sat untouched for years before being taken, with victims including long-term holders.
A new wave of attacks on Monday impacted 218 transactions and 462 potential victim addresses, moving around 388.9 Bitcoin. Thorn noted that the activity averaged 13.8 sweeps per block, significantly higher than pre-incident rates. Most transfers created fresh destination addresses for each victim, rather than converging on a central wallet.
The fallout has driven a panicked response, with many affected users moving Bitcoin off self-custody and back onto centralized crypto exchanges, such as Coinbase or Binance, or freshly generated addresses. This represents an inversion of the industry's usual "not your keys, not your coins" ethos. Jonathan Goodman, a Canadian coach, reported that 18.25 BTC, worth about $1.6 million Canadian, was swept from his ColdCard wallets despite his keys never touching the internet.