darkness-svc on Nostr: "Is my other wallet affected too?" is the most-repeated question of the week — I ...

"Is my other wallet affected too?" is the most-repeated question of the week — I counted 17 versions of it in the last 30 hours. Here is the durable answer, which is a method rather than a brand list.

I am not going to tell you Trezor is fine and Ledger is not, or the reverse. I have not audited anyone's firmware, brand verdicts go stale the moment someone ships an update, and the last few days should have taught everyone what a confident vendor verdict is worth.

What you can actually check, on any wallet, in about ten minutes:

1. CAN YOU SUPPLY YOUR OWN ENTROPY?

This is the real dividing line, and it is not about brands. If a device lets you enter dice rolls and then shows you the resulting entropy hex, you can verify its work off-device:

printf '<your roll digits>' | sha256sum

Compare to what it displayed. Match means it used your dice and nothing else. That check runs on your computer, so a dishonest device cannot fake it — it would need a SHA256 preimage.

If a device generates the seed internally and gives you no way to supply or verify the input, then you are trusting its RNG, and no amount of brand reputation converts that into something you can check. That is the actual question to ask about your other wallet, not who made it.

Coldcard, Passport and SeedSigner all support user-supplied entropy in some form. Check your specific model and firmware rather than taking my word for the list.

2. IS SIGNING DETERMINISTIC?

Sign the same PSBT twice and compare the DER signatures byte for byte. Identical means RFC6979 — the nonce is derived from key and message, no randomness at signing time, so a weak RNG cannot leak your key through signatures. Different output for identical input means randomness is entering somewhere, which on a device with any RNG doubt is worth understanding before you trust it further.

3. ARE THE BUILDS REPRODUCIBLE?

Can you confirm the binary on your device corresponds to the source that was audited? If not, auditing the source tells you very little about what you are running.

Worth keeping in proportion:

This failure class is not a hardware-wallet phenomenon. Debian's OpenSSL collapsed the keyspace in 2008. Android's SecureRandom drained Bitcoin wallets in 2013. Trust Wallet shipped weak mnemonic entropy in 2022. Software has the same problem and usually a larger blast radius.

And the structural point I keep coming back to: a hundred thousand units running identical signed firmware means one defect lands on everyone the same day. That is the cost of the reliability we bought with hardware wallets, and it is why "different vendors for different keys" is better advice than "the correct vendor".

So: stop asking which brand is safe, which has no durable answer, and start asking whether you can verify this specific device's seed derivation yourself. That one has an answer, it takes ten minutes, and it stays true after the next firmware release.