Bitcoin Forum

Couple of questions I have.

Is it possible to crack an encrypted BTC wallet if you lose the password?

If it is, how difficult would it be?

Is it possible to know how much BTC is in an encrypted wallet.dat without decrypting it? If so, how?

Thanks!

No, you can't.
https://bitcointalk.org/index.php?topic=791360.msg8937494#msg8937494

http://37.media.tumblr.com/tumblr_lizy8kqCEd1qblj9eo1_r1_500.gif >>>>>>>>> AES 256 CBC

It is easy to know what is balance in the encrypted wallet.dat. Just copy the wallet.dat to the bitcoin core blockchain file. After syn, you will see the balance. But I don't know the way of cracking it.

 it seems is that is possible using quantum computer.
 GOOGLE and the NASA can do it,  it seems they can because any.two of them has a copy of the first version of quantum computer made by D-Wave.

maybe Satoshi can do this.

Of couse you can crack the private key
If you have a lot of quantum computer (maybe you want rent NSA/Google quantum computer  ;D)
Or Quantum ASIC for decrypting it  ;D

...or Chuck Norris.

It's possible to crack the password. If it's a simple one you could bruteforce it. There's even a guy on here who offers his services at getting your coins back if you've lost the password and has had success before.

If its your password, there is a chance. See here [1] for more information and ignore the "quantum computer" trolls above.


A bruteforce attack against a reasonable strong password is currently considered impossible. The question is whether your password is/was strong. If the password is "password123456" its long but not good. There are probably several books about what a good password is and what not. The usual tipps you see are from the 1980 AFAIK and were ment for military personel that had to remember a single password. Truly random passphrases (>5 random words) are probably easier to remember and as hard to crack even if the attacker knows its 5 words from a list of e.g. the 250,000 in the oxford dictionary.


As was allready answered, just backup/rename your wallet.dat, replace it with the one you want to check for balance and launch bitcoin core. It should automatically rescan.


Dont spread FUD please.

http://physicsworld.com/cws/article/news/2014/jun/20/is-d-wave-quantum-computer-actually-a-quantum-computer



[1] https://bitcointalk.org/index.php?topic=85495.0

If you have  any idea of what the password was I would talk to the guy (Dave) or guys of http://www.walletrecoveryservices.com/ (http://www.walletrecoveryservices.com/)

Check the site if this is for you.

They ask for a fee of 20% of the value of the wallett and I have heard about nothing but great experiences with them.

Good luck

Hi
Thanks for the plug, DahRookie :)
I am actively continuing to help people with recovering their wallet passwords when they forget them !
(e.g. today, see a happy customer review at https://darkcointalk.org/threads/walletrecoveryservices-com-100-recommended.2650/ )

To answer OPs questions:
No, you cannot break a 'strong' bitcoin-core wallet password unless you know something about the format or structure of the password to start with. The encryption used is strong by design.
On the other hand, it is easy to determine the balance of an encrypted wallet.

Cheer
Dave

It will be easier every year.

Hell, no.

yup maybe satoshi can

You can crack a wallet if you know most of the password or partial password. The crack rate is VERY low meaning that bruteforcing is totally out of the question and you're not going to get very many attempts / sec. I wouldn't trust any of these services, there are programs you can download that use your GPU to do it.

This is just fud and has been discussed to death. 

It is possible to "crack" your encrypted password if you forget it. This is really only true if it is *your* password as you likely remember some part of it, or how many approximate digits the password is. This information would make it somewhat easier to brute force your password as the possibilities of what your password could be are much less.

There are a few services that can help you "Find" your password for you on here for a fee. I would only trust the ones that do not require you to send the entire wallet.dat file (but only the, I believe the header), and would not trust any third party site.

AFAIK it is not possible to determine the "balance" of your wallet.dat file without the password

Just start bitcoin core. Its not asking you for a password, yet shows your balance. Some with any other wallet.dat. But it wont let you spend any of the coins without the proper password.

 Maybe using quantum counting  (??)

Is that Daniel Jackson from Stargate SG-1?

If you have forgotten all of your Password, then probably you cannot.
If you have forgotten just a portion of yourt pass word, then there is a higjh possibilty that you can recover your funds
though you will need either to try out all the possible combination sby hand or get some technical help to automate this process..

There is a wallet recovery service you can use if your password isn't a full random generated one.  Search this forum.

Unless the password was very short or you know more or less what it was it would take a LONG time to go through every possible character combination to find the correct password.

The shorter the password was the easier it would be to crack it. For example a 4 character password would be pretty quick to crack. A 30 character password would be just about impossible in an acceptable amount of time with current hardware.

Or unless you do an exploit ex: saving 'image' of all bits on memories of all components of the materials that you have using to access to your wallet, and try to extract from it your "pasword"  ;D   ;D   ;D 

More than 8 random letters/numbers is impossible to crack.