Bitcoin Drained from Coldcards
Was your address drained?
Paste a public bitcoin address to check it against the 2,321 addresses drained across both episodes. The check runs entirely inside your browser against a hashed list. Nothing is sent anywhere and nothing is logged.
The set covers both episodes: 1,195 addresses on 30 July (blocks 960183 to 960191) and a further 1,126 on 31 July (blocks 960345 to 960369). The first window fell on the evening of Wednesday 29 July in US time zones, which is why some accounts date the theft to the 29th.
Never type a seed phrase, private key, or passphrase into this page or any other. No legitimate tool asks for one.
Most recent drain
The last address drained, in a second episode on 31 July. 250 others fell in the same block. How many people that adds up to is not knowable from the chain, since one wallet can hold many addresses.
Where the money is
The four addresses the sweep paid into. Nothing has left them.
Balances refresh every 60 seconds and stream over a websocket in between. If any tracked address spends, this page reads where the coins went and starts tracking those addresses too, following the trail one hop at a time. The headline figure only ever counts coins traced back to the theft, so a destination wallet holding other funds cannot inflate it.
Is your Coldcard affected?
Seeds generated on the firmware below were built with far less randomness than intended. Find your model and compare against the version you generated your seed on.
Coinkite\u2019s advisory covers the Mk3 and newer. The Mk2 entry comes from Block\u2019s engineering analysis, which found the same vulnerable path and no secure reseed on that model, and no patched firmware for it has been published. Coinkite dates the Mk3 exposure from 4.0.1 while Block traces it to 4.0.0; the wider range is shown here.
\nUpdating the firmware does not repair a seed that already exists. If your seed was generated on an affected version, the fix is to move your funds to a newly generated wallet.
Two things reduce the risk: adding 50 or more of your own dice rolls during seed generation, and a strong BIP-39 passphrase. Coinkite still recommends migrating. Their advisory is the authority on what to do, not this page.