Coldcard Firmware Updates Fail to Rescue Vulnerable Seeds

Coldcard, a hardware wallet manufacturer, released firmware updates 5.6.1 and 1.5.1Q on August 20 to address security flaws in seed generation.

The update closes the gap for new seeds but does not rectify existing vulnerable seeds, which were generated between March 2021 and July 2026.

Around $116 million was lost due to the flaw, with over 5,200 addresses affected. The attackers exploited predictable recovery phrases to clear Bitcoin balances from devices.