A Coldcard hardware wallet firmware vulnerability was exploited to steal about 2,100 Bitcoin, with losses nearing $130 million, and the breach was followed by large wallet movements. On-chain data showed long-term holders moved roughly 233,000 Bitcoin worth about $15 billion in the surrounding days, while about 22,000 Bitcoin flowed to exchanges. Casa Chief Executive Officer Nick Neuman said some of the transfers came from Coldcard users migrating to multisig wallets (wallets requiring multiple approvals), with Ledger and Trezor users making similar moves after the incident. Coinkite urged anyone whose mnemonic (wallet recovery words) was generated on firmware versions 4.0.1 through 4.1.9 to treat the wallet as compromised and immediately migrate to a new mnemonic. Those versions cover March 2021 to July 2026.