How to recover a Coinbase multisig wallet to Electrum?

if I have the "user seed", "user public key", "shared seed", "shared public key", and a "coinbase public key", can I recover my Coinbase multisig wallet from 2016 into Electrum following the steps in this post?

Honestly, you might wanna move this to a tech sub-board. It could get more eyes on it for better help. Just click "Move Topic" and pick a suitable board like Bitcoin Technical Support.

So, here's the deal: the Coinbase vault is basically a 2-of-3 multisig. You have one key, Coinbase has another, and the third key is shared between you two. With your two keys, you can access the funds.

If the "user seed" is your private key and the "shared seed" is an encrypted private key, then looks like you got what you need to recover that 2-of-3 multisig without hitting up Coinbase.

100% right. Users didn't get a seed phrase. They got a user seed and some public keys... but no actual seed phrases, just random numbers that look legit.

Honestly, the lack of a seed phrase isn't the big issue now. You gotta focus on getting two out of those three keys first. You’ve got the user seed key, but the shared one’s encrypted.

Yeah, it's frustrating. If only we had a seed phrase instead of this mess. But I appreciate all the help. Just a heads up, I don’t remember the decryption password, so I might be stuck.

Could be worth checking out constants.js. You might be able to tweak some.js files to get what you need. It sounds tedious tho, not sure how it’d work.

I heard they stopped supporting multisig vaults ages ago, so not sure how feasible this is now. Have you tried recovering it already?

If you can't get the decryption key, you could brute force it, or see if Coinbase can help with the seed. But honestly, good luck with that.

If you get it to work, you'd be a legend. Imagine accessing a 2-of-3 multisig with just one key. Makes you wonder if Coinbase could’ve done that too.

I might be able to handle those js tweaks, but I'm not a coder. Been through a lot already and I don’t wanna mess it up. Can’t even get the withdrawal process to start.

Sounds like you need someone who gets the decryption steps from that GitHub repo. Once you verify the password situation, then you can decide what to do next.

That's not how it works. Coinbase has the seed and the encrypted shared seed. The user usually enters the decryption key for the shared seed to get to those two out of three.

But the OP doesn't even have the shared seed or the decryption key. They only have the user seed. That's one out of three, not good enough.

Right, the second key in that scenario is the Coinbase seed. But since they’ve ditched support for multisig, accessing it might be impossible.

The GitHub tool for Coinbase multisig isn’t working anymore. I’ve tried to get it up and running, but no luck.

I think you meant to say 'shared seed' instead. Just saying.

The user seed should allow access to everything necessary for recovery. I think the security model is flawed if it can be bypassed like that.

I found a way to test decrypting the shared user seed, but no luck with the passwords. Brute forcing the password might be the only option left.