Lost Passphrase

[jegalindogt]

A friend of mine decided to encrypt his Private Key with a BIP38 protocol. And now he does not remember the Password. 18BTCs is the Amount of Bitcoins in that Wallet that is encrypted.

Any idea to decrypt that private key?

My friend is willing to give a fairly generous reward to anyone who can help him recover those Bitcoins.
My friend has, his private key encrypted, but he does not remember his passphrase.

Regards!

[bitmover]

Did you try to brute Force it?

There are some programs around that could do it, if he remembers his seed and have at least an ideia about what the passphrase could be

[cryptonerddy]

was it a paper wallet or he created it with a software?

[jegalindogt]

I think it was a Paper Wallet. But he only have the Encypted Private Key, and he know that was with a BIP38 Encryption (SHA-256 Passphrase).

[cryptonerddy]

if so then i think its not possible to brute force it currently, hence why he protected it in the first place.

[HCP]

A friend of mine decided to encrypt his Private Key with a BIP38 protocol. And now he does not remember the Password. 18BTCs is the Amount of Bitcoins in that Wallet that is encrypted.

Any idea to decrypt that private key?

Unfortunately, BIP38 is quite "secure"... unless he has a fairly good idea of what the passphrase used was and used a relatively simple password... bruteforcing is going to be a sloooooow process (like years and years). Not sure of any really reliable BIP38 brute forcing tools... but a quick search found this: https://github.com/countzero/brute_force_bip38 and this https://github.com/cculianu/brute38/

There are some programs around that could do it, if he remembers his seed and have at least an ideia about what the passphrase could be

Not applicable... OP is talking about BIP38 encrypted private keys (eg. an encrypted paper wallet)... not a BIP39 wallet with a passphrase.

[jegalindogt]

Add me to telegram HCP: jegalindogt. Maybe you can help me! Thanks!

[LoyceV]

You (or your friend) are/is going to want to read this thread: I'm BIP38 curious, please help me out!. It shows how difficult brute-forcing is, 6 random characters may be worth it at current Bitcoin value, but you can expect to pay a lot on cloud computing power.

[HCP]

You (or your friend) are/is going to want to read this thread: I'm BIP38 curious, please help me out!. It shows how difficult brute-forcing is, 6 random characters may be worth it at current Bitcoin value, but you can expect to pay a lot on cloud computing power.

Note that the search space for that challenge was only upper and lowercase letters... it did NOT include numbers or symbols... And no-one managed to crack the 6 character password in 2 years!!?!

Granted, it was only 0.5 BTC prize when BTC was worth a few hundred dollars... I'm sure that 18 BTC at today's value might be slightly more incentive


EDIT: I tried the Go cracker... it seems to average only ~10 passwords/sec on my setup.

With a charset (upper/lowercase + numbers + symbols) of: !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~.

A 4 character password has a total passphrase space size of: 84,934,656. So... "only" 8,493,465 seconds to check them all... or ~100 days... for a FOUR character password

[LoyceV]

With a charset (upper/lowercase + numbers + symbols) of: !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~.

A 4 character password has a total passphrase space size of: 84,934,656. So... "only" 8,493,465 seconds to check them all... or ~100 days... for a FOUR character password

It's a feature, not a bug! The whole point of using an encrypted wallet is that nobody can access it without your password. BIP38 is a very smart implementation to make brute forcing (almost) impossible.

[HCP]

Oh... I know. Granted, the Go cracker hasn't implemented GPU acceleration, but I doubt that would yield a vast improvement over the 10 password/sec rate that I was getting with a 4 core CPU.

I was merely highlighting the trouble the OP is going to have trying to bruteforce a BIP38 passphrase

[harnorno2]

A friend of mine decided to encrypt his Private Key with a BIP38 protocol. And now he does not remember the Password. 18BTCs is the Amount of Bitcoins in that Wallet that is encrypted.

Any idea to decrypt that private key?

My friend is willing to give a fairly generous reward to anyone who can help him recover those Bitcoins.
My friend has, his private key encrypted, but he does not remember his passphrase.

Regards!

Unfortunately, BIP38 protocol is a very strong encryption algorithm that makes brute forcing next to impossible.

The only remedy your friend have right now is to try out all the previously used passwords. Who knows, the door may magically open. And TRY ALL VARIATIONS!

[CryptAssist]

I have a unique suggestion for you. See a hypnotherapist. I know it sounds silly but if he actually knew the number in his head at one time, then he it is in there. The mind is easier to decrypt than BIP38. I had a friend who tried it for a completely different reason and said it was amazing. Took him all the back to his childhood in clear detail.

If it works, please send my "generous" reward to: BTC 3Jso7cwdzVHY9m2VQydTA9uCsfroceBNHW

[hubballi]

I have a unique suggestion for you. See a hypnotherapist. I know it sounds silly but if he actually knew the number in his head at one time, then he it is in there. The mind is easier to decrypt than BIP38. I had a friend who tried it for a completely different reason and said it was amazing. Took him all the back to his childhood in clear detail.

If it works, please send my "generous" reward to: BTC 3Jso7cwdzVHY9m2VQydTA9uCsfroceBNHW

This is the unique solution ever given by any one. But i think it can work but for that he should be knowing when he had encrypted the wallet so that the hypnotherapist can go to that particular time and recollect the data, but be sure that the hypnotherapist dont have bitcoin knowledge so that he dont cheat and take the password himself and recover your wallet and steal your bitcoins.

[Olivier_crypto]

My post was deleted, I suppose because I made a joke. The reply was serious though: if you can narrow down the password options you could then try combinations or similar stuff and try those. It's quite some money and maybe you can find someone willing to help you in that area. But if he is totally clueless about the password I think you can consider it lost.