Bitcoin Forum

Bitcoin => Wallet software => Topic started by: rtsam on March 29, 2022, 12:48:43 AM



Title: Recover passphrase from an unencrypted wallet
Post by: rtsam on March 29, 2022, 12:48:43 AM
So I have a paper wallet that has multiple wallets. BIP38 (with the same passphrase)

I do not have the passphrase / can't remember it. However, I have a empty wallet that was decrypted previously.

So my question, is it possible to figure out what passphrase was used from an decrypted private key (wif or base 58) and its encrypted counterpart?


Edit:


1A2weWHsxXB7dFHCc7TQNEauvsd3GzTvxD  (empty)

Private Key: L1VUccwGxwp1SqqXYkZamKjqcH4yD74oD4RBc26Lqwj5zu5rz4gg

Encrypted Private Key: 6PnPP4qkRMRNduWBY131PtbKFV3v9C4L7UxZF3ueZJFf48swuC6MDfPvCB

Passphrase: ?

So what I am hoping is possible, is that I am able to decode what passphrase would have been used to come up with that encrypted key. Working in reverse.







Title: Re: Recover passphrase from an unencrypted wallet
Post by: Btcspot on March 29, 2022, 01:13:38 AM
 Hi what wallet is this, electrum, bitcoin core? Are they funded, first if its unencrypted yes maybe you can extract it.


Title: Re: Recover passphrase from an unencrypted wallet
Post by: rtsam on March 29, 2022, 01:26:39 AM
bitcoin paper wallet created on bitaddress org

the unencrypted/previously decrypted wallet is empty



Title: Re: Recover passphrase from an unencrypted wallet
Post by: pooya87 on March 29, 2022, 04:18:19 AM
You won't gain any practical edge by having both the private key and the encrypted key. All you could do to the algorithm is to skip the last conversion to address/public key but that step isn't taking that much time compared to the rest of the algorithm which is a lot more expensive.

In simple terms you have to recover the password for this BIP38 key just like you recover the password for any other BIP38 key, by brute forcing it. The only possible way of doing this is to either have a very short password or have some idea about what the password was like (random alphanumeric, dictionary words, symbols,...).


Title: Re: Recover passphrase from an unencrypted wallet
Post by: HCP on March 29, 2022, 07:39:14 AM
pooya87 is totally on the money here... Unfortunately, knowing the "plain text" and "encrypted text" in this instance is of no benefit in determining what the encryption key is. You're not able to "work backwards" in this instance.

Your only option will be bruteforce.



Title: Re: Recover passphrase from an unencrypted wallet
Post by: LoyceV on March 29, 2022, 11:06:22 AM
So I have a paper wallet that has multiple wallets. BIP38 (with the same passphrase)
Do you have any idea how long the password is? BIP38 encryption is very slow to brute-force.
See I'm BIP38 curious, please help me out! (https://bitcointalk.org/index.php?topic=1014202.0): from 2015 to 2017 a reward that went up to $1000 wasn't enough to crack a BIP38 wallet with password "zLwMiR (https://bitcointalk.org/index.php?topic=1014202.msg18485829#msg18485829)".


Title: Re: Recover passphrase from an unencrypted wallet
Post by: rtsam on March 29, 2022, 01:30:03 PM
So I have been attempted to brute force it for months. No luck. I thought I was lucky and a decrypted wallet would work to speed things up.

However I had an "a ha" moment this morning. I remembered I had this old banking password I used to use (but only for my bank that I no longer have)

I guess back then I thought... bitcoin... bank. And I must have used the same one thinking I would never forget it.

PS... it was 9 characters.


It worked. So I am good now! I need a drink.

Thanks guys!!