Bitcoin users shifted tens of thousands of coins in a flurry of small transfers as a reported Coldcard-related hack continued. Researchers said the attack remained active while on-chain data showed a surge in sub-1 BTC movements, including approximately 39,600 BTC moved in small transactions — the largest such spike since the FTX collapse, according to CryptoQuant.
Surge in Sub-1 BTC Transfers
On-chain activity indicated an unusually large volume of transactions under 1 BTC, totaling about 39,600 BTC. CryptoQuant characterized this as the biggest wave of sub-1 BTC moves since the aftermath of FTX’s failure in late 2022, a period marked by heightened self-custody and risk management behavior across the market.
Attack Reportedly Ongoing
Researchers monitoring the incident warned that the attack tied to the Coldcard ecosystem remained active. The ongoing nature of the threat appeared to prompt users to reorganize holdings into smaller amounts — a pattern commonly seen when market participants test addresses, rotate wallets, or compartmentalize exposure during security events.
Why It Matters
- Elevated small-size transfers can signal widespread caution among retail and smaller holders.
- Spikes in sub-1 BTC activity have historically coincided with security incidents or market stress.
- Sustained on-chain reshuffling may affect transaction volumes and fee dynamics in the short term.
Background: Coldcard
Coldcard is a Bitcoin-focused hardware wallet brand used for self-custody. Reports of a related hack have raised security concerns and triggered precautionary fund movements. Further details on the scope and vector of the attack were not immediately available.