Question about CoinJoin

[BlackHatCoiner]

I've been searching a mnemonic for a hunt. I found out that it's been generated with Wasabi. To cut a long story short, I know 10 out of 12 words, but I don't know the derivation path. I just know that it was generated with Wasabi.

Here's my question: Could it be deeper than 76? Once I recover a seed with Wasabi, it writes the first 76 public keys on the Wallet.json. If I receive money on one of these, then It'll show it to me on the user interface. But if I receive funds on m/84'/0'/0'/10000 for example, I will never notice it.

I had a discussion with another player of the hunt, and he told me that due to coinjoin, once coins are sent to an address they can skip hundreds of addresses. Isn't coinjoin just for improving your privacy? I didn't understand that.

Knowing that the address won't be after a specific derivation path will save me a thousand hours of brute forcing.

[Oshosondy]

Let me share my own opinion about coinjoin, in a particular transaction you make, it is not only your addresses that is participating in the transaction, the transaction will be in batches where many participants transactions will be included (I think 100 participants). The transaction will be mixed in such a way the address you are paying to will not be paid by your address, but by another address. To get the address that pays you will be difficult, to get the address you paid will also be difficult. This will be in a way that your transaction will be diverted away from the address you are paying while another transaction is used to pay into your address. This is a good way transactions can be mixed, a way bitcoin privacy is existing.

About seed phrase, there is nothing concern wasabi about seed phrase, only what you need to do is to protect your seed phrase. If it is compromised (if 10 words are known, it can be bruth forced easily), it can be used to know the address that pays but not reasonable because you still do not know who is who.

[BlackHatCoiner]

the transaction will be in batches where many participants transactions will be included (I think 100 participants)

Is this a CoinJoin transaction? How deep can it be? Could it choose an address from 10000th index?

[Oshosondy]

Is this a CoinJoin transaction? How deep can it be? Could it choose an address from 10000th index?

I am not sure how deep a coinjoin transaction can be, but that transactions are probably coinjoin, 0.01btc is the minimum amount you can use for coinjoin transactions. What I know about coinjoin is all I have explained above, I do not know anything about how deep it can be. But I know it is possible for coinjoin to have 100 participants which will make it have 50 transactions to coinjoin. This is the depth I can relate to it.

[BlackHatCoiner]

10 of 12 words? Wasabi force you to insert password when create wallet which used to encrypt the wallet and as 13 words of BIP39 seed/mnemonic.

It didn't force me to insert anything. I left password field empty and it created it normally.

Looking at my own wasabi wallet (where i tried few CoinJoin in past), all the index position is less than 100 after CoinJoin.

So I guess I'll have to brute force the first 100.

[DaveF]

Like ETFbitcoin if you installed the "stock" wasabi wallet and did the basic coinjoin setup then there is nothing that special about how deep the index is.
But, as always there are ways to change it, and it is open source so the person who setup the "hunt' could have changed the derivation path to anything they wanted to.
You also don't know what (if any) other changes were made.

-Dave

[BlackHatCoiner]

You also don't know what (if any) other changes were made.

I know that once you import the mnemonic, Wasabi will show you funds. If bitcoins are on the 10000th index, it won't show me anything. Once you import it, it'll load you the first 76 indexes. (it can be seen from the wallet.json)

I know that A) it's on the 1st account and B) derivation path can't be higher than 76 due to the reason above.

[DaveF]

You also don't know what (if any) other changes were made.

I know that once you import the mnemonic, Wasabi will show you funds. If bitcoins are on the 10000th index, it won't show me anything. Once you import it, it'll load you the first 76 indexes. (it can be seen from the wallet.json)

I know that A) it's on the 1st account and B) derivation path can't be higher than 76 due to the reason above.

You did not read what I said.
If I compile my own version of Wasabi wallet and throw some funds out there for a "hunt" I can do whatever I want the the mnemonic and the derivation path a a few other things.
You can see me typing in the mnemonic into my wallet and copy it word for word into yours yet because I set some custom things in the code you will generate an entirely different bunch of addresses.

So when doing these hunts you have to rely on the fact that the person setting them up is not just in it for laughs as you spend hours (days?) searching for something you will never find.

-Dave

[BlackHatCoiner]

You can see me typing in the mnemonic into my wallet and copy it word for word into yours yet because I set some custom things in the code you will generate an entirely different bunch of addresses.

He said that he didn't choose any custom settings. He did it with the simple way. He also didn't use any passphrase, only the 12 words. He never stated that he chose the 1st derivation path, but said that it'll be difficult for anyone who will try to brute force it. This is what made me think that the money are on a deeper path. I just don't know how deep I should search.