Coinkite warns Coldcard Mk3 users after $38 million Bitcoin sweep
Canadian hardware maker Coinkite urged Coldcard Mk3 users to migrate funds following a potential seed-generation vulnerability in firmware version 4.0.1 through version 5.0.3. The warning comes as security analysts examine an unexplained sweep of 594.48 BTC, worth $38.3 million, executed across 500 transactions within a three-block window. Experts suspect low entropy in key generation allowed an attacker to brute-force affected wallets, prompting urgent calls for users to move their assets.
Key takeaways
- 1Coinkite identified a potential seed-generation risk in Coldcard Mk3 firmware versions 4.0.1 through 5.0.3.
- 2Security experts are investigating a coordinated sweep of 594.48 BTC worth $38.3 million from single-signature wallets.
- 3Newer Coldcard models including Mk4, Q, and Mk5 are not affected by the reported firmware issue.
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Why it matters
Hardware wallet flaws undermine the core security assumption of crypto self-custody. Investors holding self-custodied Bitcoin should audit wallet firmware history and migrate vulnerable seeds to secure devices to prevent potential exploit losses.
Discussion
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