According to CoinMeta, Coldcard has released firmware versions 5.6.1 ( mk4 / mk5 ) and 1.5.1q (q), which require new mnemonic phrases to include at least 65 irregular key presses, 50 physical dice rolls, or 128 physical coin tosses as a source of user entropy. The new firmware adds psbt verification before signing, strengthens the usb connection, delta mode isolation mechanisms, and initializes the random number generator. Coldcard reminds affected users to generate brand-new mnemonic phrases after updating their devices and migrate their funds to a new wallet, while also recommending that all users verify the firmware signature.