p2sh-segwit multisig with ledger nano s, weird change path warning

[pabloP]

Hello everyone,

I setup a multisig wallet with some friend. We are using p2sh-segwit and each with a ledger nano s.

But when we sign transaction we get a weird warning on our ledger:
Unusual change path, and then the derivation path is displayed. Finally we need to confirm we are sure about it.

The thing is we can just confirm it will process the transaction just fine.
But I was still wondering is that could become a problem at any point?

To let you know also we tried to create transactions with or without change address and in both case we have the warning.

Thanks for your insights on the question.

-Pablo

[HCP]

Is the error message showing on the Ledger device itself? If so, it's simply because the Electrum wallet will be using a derivation path that the Ledger isn't expecting. I think the Ledger devs may have put something into the Nano S firmware to do a sanity check on the addresses being generated to prevent issues with external wallets creating addresses on "non-standard" derivation paths. (Might explain this issue which mentions derivation path "locking")

I'm not 100% sure what the derivation path that Electrum is using for hardware wallet based multisig change addresses... but do the change outputs actually end up back in your wallet? Can you see them in the change addresses listed for the multisig wallet? If so, I wouldn't be too concerned. It'll just be because you're using a MultiSig setup and Ledger doesn't really do multisig by default.

If you're really concerned, I'd be tempted to query the Ledger support via their website or github issues list or on Reddit (they're more active there)

[pabloP]

I see. Yep it does only display on the Ledger and all is good with the outputs going into the change address or staying in the same address if change deactivated.

Thanks your help, I guess I'll poke Ledger support just to be sure.

[AB de Royse777]

I see. Yep it does only display on the Ledger and all is good with the outputs going into the change address or staying in the same address if change deactivated.

Thanks your help, I guess I'll poke Ledger support just to be sure.

Ledger does not support a multiSig address yet. In fact I do not see any reason for them too.

You can create a multiSig wallet using a desktop application like Electrum. It's very easy process. You need to define how many keys (cosigners) including you needed then:
Do your part until you get your Master Public key. Save the information of Seed and Master Public key.
Ask the other users to do the same.
Once you all have your Master Public Keys then you can open your MultiSig wallet.

By the way, before sending a large sum send a small amount of BTC using 1 sat/byte fees. Test if you can initiate a successful out transaction from the multiSig wallet. Once you are confirmed then start depositing your coins there.

I hope it helps.

[HCP]

I see. Yep it does only display on the Ledger and all is good with the outputs going into the change address or staying in the same address if change deactivated.
Thanks your help, I guess I'll poke Ledger support just to be sure.

Having thought about this a little more, I would guess that what is happening is because your Ledger is not able to derive the "change" address itself from it's own Bitcoin master key and derivation path (it has no idea of the other co-signer keys so cannot replicate the combined multisig wallet addresses), it thinks that you're creating a change address on a non-standard derivation path.

Ledger does not support a multiSig address yet. In fact I do not see any reason for them too.

It's true they don't in their Ledger Live software... but you can create MultiSig sig wallets in Electrum in conjunction with Hardware Wallets.

~snip multisig instructions~

I hope it helps.

I think you missed the part where the OP stated he had already created a MultiSig wallet... and was simply getting an unusual message when attempting to sign a transaction.