Coldcard Releases New Firmware Fixing Mnemonic Generation Attack, Advises Migration of Old Mnemonics

August 20 news, hardware wallet manufacturer Coldcard has released a new firmware version, with version 5.6.1 for Mk4/Mk5 devices and version 1.5.1Q for Q devices. This version follows the emergency patch released on July 31 and comes after three weeks of continuous review. The company once again apologized to users who suffered severe financial losses due to the "mnemonic generation attack." The new version requires users to provide a source of entropy each time a new mnemonic is generated, including at least 65 unpredictable keystrokes at time intervals, 50 dice rolls, or 128 coin flips, and combines this input with entropy sources provided by STM32 TRNG, SE1, and SE2.