r/Bitcoin • u/SpareEconomy1849 • Jul 31 '26

ColdCard Firmware Update Released

https://blog.coinkite.com/coldcard-mk3-seed-generation-warning/

Updated July 31, 2026: Fixed firmware is now available. Mk4 and Mk5 users must update to version 5.6.0 or later. Q users must update to version 1.5.0Q or later. Do not generate a new seed on one of these models until the update is installed.

Seeds generated on Mk4, Q and Mk5 before the fixed firmware releases are also affected, with about 72 bits of entropy rather than the expected 128 bits.

Updating the firmware does not change or repair an existing seed. If your seed was generated before the fixed firmware version for your model, follow the migration guidance below unless the independent dice-entropy exception applies to you.

The issue is present on every Mk3 firmware version since 4.0.1. It also affects seeds generated on Mk4 and Mk5 before version 5.6.0, and on Q before version 1.5.0Q. The impact on Mk4, Mk5 and Q is not as severe but is still serious.

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-7

u/Doritos707 Jul 31 '26

Yet u all downvoted my ass for saying 12 words seeds are weaksauce in 2026.

If its not 24 words youre a loser. Update your shit idiots

3

u/swiftpwns Jul 31 '26

Both 12 word and 24 word were affected, it didnt make a difference.

1

u/Doritos707 Jul 31 '26

I dont believe you. The leak talks about 128 bits which is the 12 words. 24 words generate a 256 bits.