Coldcard hardware wallets had a firmware flaw that made keys guessable (about 40 bits of security instead of 128). Attacks in late July and early August 2026 took roughly 1,367 BTC (about US$89 million) from around 4,585 wallets. Coinkite has released a fix (1 August) and says it cannot guarantee the other models are fully safe. Owners should check model and firmware version, move coins to a new seed on an unaffected device, and test with a small transfer first. Ledger, Trezor, Bitkey and Jade report no impact. This matters only if your business or you hold crypto in a Coldcard; otherwise it is background.