Topic: Lost my "12 Word Phrase / Seed" for coinbase commerce - Need help (Read 377 times)

As far as I can tell... the problem you're going to run into is that the "xprv" that you have access to in the Electrum wallet is going to be an "Account Extended Private Key" derived from your 12 word seed... and not the actual BIP32 "root key".

This means that the derivation path for this extended key will be the equivalent of the BTC derivation path of m/44'/0'/0' (or m/49'/0'/0' or m/84'/0'/0', depending on if it's using Legacy, Nested Segwit or Native Segwit respectively).

Now, according to this post by "coinbasesupport" on reddit: https://www.reddit.com/r/CoinBase/comments/i5sl3b/mods_is_coinbase_commerce_bip39_bip44_complaint/g7x6vnp/
It would seem that the ETH (and ERC20 token) payments eventually end up in the address derived at m/44'/60'/0'/0/0


As these derivation paths are all hardened, you cannot derive the m/44'/60'/0'/0/0 address starting from the m/44'/0'/0' derivation path that the extended private key stored in the Electrum wallet represents.


TLDR; There is simply no way you can get from "what you have" to "what you need"

Hello,

2 years later my lost ETH are worth 13000 EUR (2018 it was 800 EUR) and my will to get them back is back again either.

https://i.ibb.co/557mJKr/Bildschirmfoto-2021-05-15-um-09-24-07.png

Some of you had nice ideas, but I dont think I am able to handle this alone. Is there anyone that would help me for a reward ?
I pay a reward of 1000 EUR if its successfull to get them back to the one, who helped me out.

What I got at this moment:

-> Full access to coinbase commerce account (Password, 2FA)
-> A full working electrum wallet that is combinend with that coinbase commerce account, but which is not showing the seed due to the option is grayed out. I am stillable to transfer my coinbase commerce btc amounts with that.
https://i.ibb.co/S3SGPjh/Bildschirmfoto-2021-05-15-um-09-26-59.png

-> Access to stored wallet file
-> XPRV and XPUB in bip32 generated from electrum out of my seed in 2018
-> A list of exported private keys from electrum
-> Infos about the transactions generating the ETH, which seem to be lost due to missing seed phrase
https://etherscan.io/tx/0x0c8785c60993e65fdff9ca4d7ab041551226c9d2ff147671b6a5c056cc581b35
https://etherscan.io/tx/0x36bef58f1708c9b22f1b3883c9c2d8a8654d01f75c49d0c56d500c1755d3047c

What I do not have:
-> The seed (12 words)


Is there any way to get this done ? I only need to transfer the money out of those two eth transactions to a coinbase account to sell the eth there.


Regards
Tim

The issue with using a "non Electrum" 12 word seed mnemonic in Electrum... is that you need to select the "BIP39 seed" option. When you do this... Electrum DOES NOT save an encrypted copy of the seed mnemonic into the wallet file like it does when you create a default Electrum seed (which will be non BIP39 compatible).

What Electrum does is convert the BIP39 seed mnemonic into an "xprv" and it will save that xprv into the wallet file... this is why the "seed" option is greyed out in Electrum if you're using imported seed mnemonics.

However, it might be possible to use that xprv to derive the private keys needed to get access to the ETH. Note that this is likely to be quite a fiddly process... probably not going to be a "plug and play" quick import into a wallet type exercise and will likely require some knowledge of derivation paths used by Coinbase to derive the ETH private keys/addresses etc.

What you definitely WILL NOT be able to do, is to convert the xprv back into the original seed mnemonic... it's just not possible due to the use of "one-way" hashing functions etc.

Unfortunately I have no idea as I'm not so advanced. I hope someone can give a bit more info about the case.
It's also interesting for me.

Don't use such sites ever again when dealing with private keys that may or may not have actual balance.. http://bip32.org/ might be open source, but that doesn't mean that it is safe. It doesn't even have HTTPS.

What you can try is the following: (Emphasise on try , as i highly doubt that this will work)

Download this library: https://github.com/ethereumjs/ethereumjs-wallet

put the extended bip32 privkey in there and generate a couple of private keys + their corresponding adresses. Depending on the derivation method used by coinbase, you might find your balance. It's worth a try.

---

Would that also be possible with just an xprv? I don't think OP has any "normal" private keys. (Forgive my ignorance here, just wondering.  )

Doesn't sound good, I was thinking that if you have your private keys and you have the password should be possible to generate the seed from the private key (the private key is generated from the seed).

See here :

I'm not entirely sure what you're trying to do.

Did you download and use electrum externally, or is it implemented IN "Coinbase Commerce"? I'm rather confused since you first mention you use Electrum, and then say you still have all your bitcoin in "Coinbase Commerce".

---

Or did you "import" that seed into electrum, and then forgot what the seed was exactly, is that it?


How did you create this electrum wallet in the first place? Did you import the keys or the seed?



Yes. LTC & BTC-Cash are both "forks" of Bitcoin. (Well LTC isn't really, a fork i think, but it's basically a copy of BTC too.), and thus they work the exact same way as BTC.

Ethereum also uses SECP256K1. Which means that you can use a "BTC" generated private key to generate an ethereum adress as well.
See https://ethereum.stackexchange.com/questions/6520/can-i-use-the-same-private-key-for-ethereum-and-bitcoin

But if that key will actually have any balance.. I'm not so sure. That seems pretty unlikely.

---

EDIT:

I just tried the following; I generated a extended private key using https://iancoleman.io/bip39/.

I then imported the xprv key into https://www.mobilefish.com/download/ethereum/hd_wallet.html (DO NOT DO THIS WITH YOUR ACTUAL KEYS, ALWAYS CHECK THE SOFTWARE YOU'RE USING!)
Which gives the following *first* public key;

Which if you "decode" the first private key in https://iancoleman.io/bip39/
Using https://iancoleman.io/bitcoin-key-compression/

Gives;

Is the same? So yeah, if you have a XPRV key, you should be able to generate your ethereum adress from that.

That would be easy...

in my case the field "seed" is greyed out

I'm not an expert but if you go into Electrum (it's not clear if you have access to it or only to your wallet trough coinbase)and choose from the menu Wallet>Seed, and you enter your password you should have access to the seed again.

I guess you have read trough this but still :
https://www.reddit.com/r/CoinBase/comments/91d9o5/coinbase_commerce_lost_recovery_phrase_have/

Dear forum visitors,
I really need your help. I hope somebody can give me some advice.


Ive got a coinbase-commerce account. When I registered to this services they gave me a 12 word phrase to create the wallets.
At the start I just used "electrum" wallet to receive bitcoin. This wallet still exists and is usable (I have access to my BTC at coinbase commerce).

BUT
I also received some ETH money and now wanted to withdraw this money. The problem is that I dont have the 12 word phrase anymore and I cannot withdraw the money without it.


Coinbase commerce delivers one "12 word phrase" identical for all crypto currencys they accept for me at registration. My idea was that I could gain access to the ETH coin due my xpriv / xpub key, that I could gain from the btc wallet file, which I still have access to.
The weird thing is that "electrum" offers a method to read out my "seed / 12 word phrase" but for this wallet its "greyed out". Even in the wallet file the line called "seed: ......." isnt existing.
BUT the wallet is working. I could transfer my BTCs from it to another wallet and I still receive new payments there successfully. Its not "readonly".


My question now is:
If coinbase delivers the same mnemonic seed (12 word phrase) for alle currencys (ETH, BTC, BTC-Cash, LTC) could there be a chance, that even the private (WIF-Key) could be the same and could be used for other currencys as well ?

Is it possible to generate a ETHEREUM private key that I could use in JAXX to transfer the money from this btc wallet key ?




PS: Coinbase Support told me they cannot help me, because they dont save the "private sentence / 12 word sentence / security sentence".