Coldcard Firmware Update Exposes Hidden System Failure

A recent firmware update to Coldcard hardware wallets caused thousands of Bitcoin wallets to be emptied in July this year. However, it wasn't the wallet's design that failed but rather an earlier layer of the system. Jonathan Goodman, a user, was alerted to the issue on July 29 when he heard about the problem.

The update, written in 2021, was not the cause of the failure but rather the trigger that exposed the underlying issue. The quietest layer of the system failed earlier, and the firmware update simply revealed it. Goodman assumed a critical bug had been introduced, but the actual problem was more complex.