Recovering BTC from an old Coinbase multisig Vault

[hawperify]

Hello, this may be a long shot, but I was looking for information for retrieving 1 btc from an old Coinbase Vault account.

Back in 2015 Coinbase started the 2 of 3 multisig Vault accounts. I transferred a bitcoin into the account to test it out (had value of ~$250). I had tried to take it out of the vault, but had some weird issues with the secondary email, and eventually kind of forgot about the whole scenario.

Fast forward a few years (wow, time goes fast) and I had completely missed all of Coinbases emails involving stoppng multisig Vault support. Now I'm trying to put together whether it's possible at all for me to regain access. Coinbase I beleive deleted the key they had on their end, so it's up to me to find the other 2 and hopefully regain access. Would the 2 keys on my end be a seed and password combo?

I know when I deposited the BTC. I have some potential seeds that could contain the bitcoin, however I'm pretty sure there was also a password on top of the seed. Does anyone know if the old multisig vaults used a 12 or 24 word seed? Also, was wondering what would be the best way to go about checking the seeds, along with various password combinations for a BTC balance? Did Coinbase have any particular requirements for password length, special characters, etc? It was so long ago that my memory of the specifics is fading, but I know it has to be some variation of passwords that I used to use...

Any pointers, tips or suggestions would be GREATLY appreciated!

[1714019220]

1714019220

[1714019220]

1714019220

[DaveF]

IIRC it was a 2 of 3 multisig wallet.
You had 2 keys Coinbase had 1, so with your 2 keys you could move funds.
There was also this option: https://coinbase.github.io/multisig-tool/
For you to dig through and get to your funds.

If you have your seeds you should be able to recover your funds.
Sorry I could not be more helpful

-Dave

[Findingnemo]

Does anyone know if the old multisig vaults used a 12 or 24 word seed? Also, was wondering what would be the best way to go about checking the seeds, along with various password combinations for a BTC balance?

Any pointers, tips or suggestions would be GREATLY appreciated!

The vault which I used in the past doesn't have any recovery seeds, just emails are enough to approve the withdrawals so I am not sure that it was 12 or 24 words seed but coinbase doesn't have any of those credentials stored so you are responsible for passwords and recovery seeds which were used at the time of creating multi sig vault.

It means you lost the BTC even if you had!

https://coinbase.github.io/multisig-tool/


-Dave

The tool is not working anymore? I can only see the error page and also the same result I got when I clicked the tool link from their official blog.

[DaveF]

This is what I see when I go to the tool page:



I have not entered any info in it, since I don't have any close by, but I can test later when I get home to see if it works.
Are you not getting that page or are you getting an error when you enter data?

As I said, it's been a few years so I would have to go looking for my old paper work, with the keys, if I still even have it.

-Dave

[o_e_l_e_o]

So, Coinbase multisig vaults were a 2-of-3 multisig. One key was held solely by Coinbase. One key was held solely by the user. The third key was held by both Coinbase and the user in an encrypted form, with the password you have being the decryption key. When you logged in to the vault, you used your password to decrypt the shared key, which allowed you to make transactions on Coinbase's website using Coinbase's key and the shared key.

Based on that, a seed phrase and a password alone are not going to be enough to access your coins. You also need the shared key which your password decrypts. If you do not have this backed up as well, then your only hope is going to be to ask Coinbase nicely if they still have it stored and can send it to you.

I also don't think Coinbase provided a seed phrase at all for the user key; I think it was an actual private key. You should therefore have two strings of seemingly random letters and numbers, one which will be your user key and the other which will be your encrypted shared key.

[hawperify]

Thanks for the replies and infos. I guess my memory is failing, I thought when I created the vault it gave me a seed and a secondary private key with password? But if was actually just two private keys, then it's probably lost to the sands of time.

Does anyone know what the screens looked like during the vault creation process from that time period? This would have been early 2015, when Coinbase first released their multisig vaults. My private key handling was poor at that time, but I've got a few potential strings to try. Going to pull an old computer out of storage and see if I left any clues on there... Fingers crossed, although at this point it's looking a little grim.

Thanks again!

[o_e_l_e_o]

Here's an archive of the blog post from Coinbase announcing their multi-sig vaults. It has some pictures of the set up screens on it as well: https://web.archive.org/web/20150208065852/http://blog.coinbase.com/post/101266587127/introducing-multisig-vault-you-can-now-control#_=_

And here is an archive of the actual multi-sig vault set up page itself: https://web.archive.org/web/20150213030751/https://www.coinbase.com/multisig

As you can see, nowhere does it talk about seeds or seed phrases, but rather just about private keys, but I could be mistaken.

[effin_new_guy]

https://coinbase.github.io/multisig-tool/


-Dave

The tool is not working anymore? I can only see the error page and also the same result I got when I clicked the tool link from their official blog.

The Coinbase Multisig tool on Github does not work due to an SSL handshake error with an api at bitpay.com. here is a screenshot https://imgur.com/USmIsTO
It may be possible to restore the BTC to an electrum wallet.   If I figure that out, I will share the details.  

Here is a snippet of the email I received from Coinbase indicating the steps to access a multisig vault.

Code:

How do I access my multisig vault?
- Log in to your Coinbase account at www.coinbase.com. You cannot access your multisig vault using the mobile app.

- Navigate to the “Accounts” tab from the top of the screen.

- Select your multisig vault from your list of accounts.

- Press the “Withdraw” button on your multisig vault.

- Select one of your other non-multisig Bitcoin accounts to transfer your funds to, enter in the amount to transfer, and any two factor authentication codes if needed. Then press the “Continue” button.

- On the next screen, enter your vault password into the password field, then press the “Approve” button.

- Once approved, your withdrawal will enter the 48-hour waiting period before the funds are transferred. There is no way to bypass this waiting period.


What if I don’t know my vault password?
If you don’t know your vault password, you can instead copy/paste the user seed into the password field. This will allow you to approve your withdrawal. The user seed was provided to you when you created your multisig vault.


Where do I find my vault password or user seed?
Your vault password is the phrase you chose when you created your multisig vault. The user seed is a string of numbers/letters that was provided to you during the creation of your multisig vault. You should have stored or saved both of these pieces of information when you created your vault.


What if I forgot/lost my vault password or user seed?
Unfortunately, Coinbase cannot provide or recover your vault password or user seed to your multisig vault. This has always been the case for multisig vaults. The multisig vault specifically puts you in control of your own security, and Coinbase does not have access to your vault credentials.

Because the vault cannot be accessed without these credentials, if you have forgotten/lost BOTH the vault password AND the user seed, your vault funds will be inaccessible. We apologize that there is nothing further we can do to help in that case.

According to the email, a "user seed" can be used in lieu of a password to approve a transaction which makes no sense to me because that would essentially turn a 2 of 3 wallet into a 1 of 3 wallet?  or is it still 2 of 3 because the user seed must sign two times?    Unfortunately, all of this assumes one is using the Coinbase UI (or the multisig tool) both of which are no longer functional.  
Hope this helps

[DaveF]

It is as stated.
You had one seed, coinbase had one and both you and coinbase had one (that required a password).
If you have the 2 that you should have then that is all you need.
IIRC there are other ways of getting what you need.

On a side note the 525 error means that for some reason you do not have the same SSL protocols on your browser that the server has.
However, here it is probably because insight.bitpay.com now redirects someplace else.
 
What exactly do you have in terms of keys?

-Dave

[effin_new_guy]

On a side note the 525 error means that for some reason you do not have the same SSL protocols on your browser that the server has.

What exactly do you have in terms of keys?

-Dave

I agree in regard to the 525 errors however please considering the following URLs.

I took one of the lines from the screenshot  does NOT display...   https://insight.bitpay.com/api/addr/3HYtTaezqBrQDPwEzaCassqu1hhg1AZFtk/utxo

and was able to format it into something that displays a web page

https://bitpay.com/insight/#/BTC/mainnet/address/3HYtTaezqBrQDPwEzaCassqu1hhg1AZFtk

So even if I were able to manipulate the cipher suite on my machine, I am not sure the api is still functioning at the URL the multisig Github tool is referencing. 


Funny you ask about what keys I posess, I was just working on posting the specific on another thread. 
https://bitcointalk.org/index.php?topic=5381583.msg59002408#msg59002408

[HCP]

So even if I were able to manipulate the cipher suite on my machine, I am not sure the api is still functioning at the URL the multisig Github tool is referencing. 

The source code for the multisig-tool is available... so theoretically, it should be easy enough to either modify the code to point to a different domain that is also using the "Insight API", but is still functional or you could setup your own. (This would require a full Bitcoin Core node etc).

Alternatively, you could modify the code base to use a different API to retrieve the required info (essentially it is just generating addresses and retrieving UTXO's so it can construct a transaction to send all your coins).


In any case, you will still need your vault password to decrypt the "shared encrypted seed". Without that password, recovery will not be possible using this tool as you simply won't be able to sign the transaction with the required number of signatures.

[effin_new_guy]

If anyone attempting to recover BTC from a Coinbase multisig vault happens to find this thread, I can confirm this github project worked for me. 

https://github.com/pilsnerbeer/multisig-tool-fixed

I have absolutely no affiliation with the github user. 

I had everything I needed all thee public keys, the users seed and the shared encrypted seed as well as the password used to encrypt the shared seed. 
If you don't have the required items listed above, this solution won't work for you.   

One issue that almost tripped me up is the following:  when I attempted to send BTC from a multisig wallet ( Legacy (P2PKH): addresses start with a 1) to a newly created wallet (Native SegWit (bech32): addresses start with bc1), the process did not complete. 
When I used a wallet address that starts with a 3  (Nested SegWit (P2SH): addresses start with a 3)  the process worked. 

see the article below on wallet address types

https://help.crypto.com/en/articles/4056348-send-and-receive-btc-ltc-difference-between-segwit-and-legacy-address