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Bitcoin => Bitcoin Technical Support => Topic started by: Talbot49 on December 06, 2013, 07:50:40 PM



Title: Is it possible to brute-force a private key missing 1 number or letter?
Post by: Talbot49 on December 06, 2013, 07:50:40 PM
Hi guys,

Ok so I booted Ubuntu on my laptop to generate a key pair offline, with the intention of printing it, but my printer didnt work so I ended up copying them by hand. But now I'm a little paranoid transferring bitcoin into that wallet because even though I checked my private key 3-4 times to be sure it was the written with no errors, there is still a 0.1% chance I did a mistake and I intend to store them for years so it kinda sucked that there is a very small chAnce, but still, that when I'll be willing to take them out, my private key will not work lol.

So my question is this:

In that rare case, would it still be possible to crack the private key with some kind of programs, knowing that probably only one letter/number is incorrect or missing?

In fact I bought a printer to do it again but I'm unable to boot ubuntu a second time (I deleted it after I did that process)

So if my private key would be crackable, I will stop trying to boot ubuntu again because it is a real pain in the ass. I tried everything. Looked everywhere on the ubuntu forums and found nothing. Even wrote my own topic.. If some of you are good with ubuntu and think they could help,
here is the link of my problem with ubuntu: http://ubuntuforums.org/showthread.php?t=2192098

Thanks


Title: Re: Is it possible to crack a private key missing 1 number or letter?
Post by: Akka on December 06, 2013, 07:54:16 PM
Use an Offline PC, import the priv. Key. If it worked you did everything right.

After that delete the Wallet from the offline PC.


Yes, if only one letter is missing it would be really easy to guess it.


Title: Re: Is it possible to crack a private key missing 1 number or letter?
Post by: rarkenin on December 07, 2013, 01:00:21 AM
Yes. Like a password, you can try every possible single change that would result in a valid private key being output. One of those will eventually be the right one.


Title: Re: Is it possible to crack a private key missing 1 number or letter?
Post by: Talbot49 on December 07, 2013, 02:47:03 AM
Yeah but you understand I'm not talking about missing one letter or number at the end right?. I'm talking about a 30ish numbers/letters private key, missing a number or letter anywhere in it, or maybe not missing, but the wrong number/letter somewhere in the private key. That is a shitload of combinations to guess by yourself lol.

But is there is some program to crack those type of things if you know almost all of it? Trying different things until it matches your public key? I hope it does so I would get the relief that even if I screwed up one element, I will be able to recover my private key, and at the same time my savings.

Just need a convincing answer about such programs before I transfer them into that wallet.

Thanks


Title: Re: Is it possible to crack a private key missing 1 number or letter?
Post by: RoxxR on December 07, 2013, 03:41:57 AM
Throw in a bounty and I'm sure somebody will be able to code such a little program for you.


Title: Re: Is it possible to crack a private key missing 1 number or letter?
Post by: grue on December 07, 2013, 04:51:53 AM
In your case, there's no need. The private key import format contains a checksum. All you need to do to verify whether your key was copied correctly is import it into bitcoin-qt. it will prompt you if the checksum mismatches.


Title: Re: Is it possible to crack a private key missing 1 number or letter?
Post by: Abdussamad on December 07, 2013, 10:58:09 AM
Yeah but you understand I'm not talking about missing one letter or number at the end right?. I'm talking about a 30ish numbers/letters private key, missing a number or letter anywhere in it, or maybe not missing, but the wrong number/letter somewhere in the private key. That is a shitload of combinations to guess by yourself lol.

But is there is some program to crack those type of things if you know almost all of it? Trying different things until it matches your public key? I hope it does so I would get the relief that even if I screwed up one element, I will be able to recover my private key, and at the same time my savings.

Just need a convincing answer about such programs before I transfer them into that wallet.

Thanks

No! Don't rely on brute forcing when just generating a new key pair will do. I don't know whether you realize this or not but you can run ubuntu straight from the DVD i.e. you don't have to install it on your hard drive.

Maybe it would be better if you stopped this whole thing? You are liable to loose your coins because you made a mistake.


Title: Re: Is it possible to crack a private key missing 1 number or letter?
Post by: Talbot49 on December 08, 2013, 01:55:28 AM
Yeah but you understand I'm not talking about missing one letter or number at the end right?. I'm talking about a 30ish numbers/letters private key, missing a number or letter anywhere in it, or maybe not missing, but the wrong number/letter somewhere in the private key. That is a shitload of combinations to guess by yourself lol.

But is there is some program to crack those type of things if you know almost all of it? Trying different things until it matches your public key? I hope it does so I would get the relief that even if I screwed up one element, I will be able to recover my private key, and at the same time my savings.

Just need a convincing answer about such programs before I transfer them into that wallet.

Thanks

No! Don't rely on brute forcing when just generating a new key pair will do. I don't know whether you realize this or not but you can run ubuntu straight from the DVD i.e. you don't have to install it on your hard drive.

Maybe it would be better if you stopped this whole thing? You are liable to loose your coins because you made a mistake.

Yeah but I generated it offline and I can't do that anymore since I'm not able to run ubuntu anymore. And I don't have an offline pc just to do that like some people suggest.

There is some people able to brute-force some brainwallets isn't it the same process if you have a whole private key missing an element or having a wrong element? There has to be a way to do it. There is like 99.5% I wouldn't need it but would like to know it's possible!


Title: Re: Is it possible to crack a private key missing 1 number or letter?
Post by: User705 on December 08, 2013, 01:57:33 AM
Yeah but you understand I'm not talking about missing one letter or number at the end right?. I'm talking about a 30ish numbers/letters private key, missing a number or letter anywhere in it, or maybe not missing, but the wrong number/letter somewhere in the private key. That is a shitload of combinations to guess by yourself lol.

But is there is some program to crack those type of things if you know almost all of it? Trying different things until it matches your public key? I hope it does so I would get the relief that even if I screwed up one element, I will be able to recover my private key, and at the same time my savings.

Just need a convincing answer about such programs before I transfer them into that wallet.

Thanks
Yes extremely easy.
https://bitcointalk.org/index.php?topic=316979.0


Title: Re: Is it possible to crack a private key missing 1 number or letter?
Post by: Talbot49 on December 08, 2013, 04:16:18 AM
Yeah but you understand I'm not talking about missing one letter or number at the end right?. I'm talking about a 30ish numbers/letters private key, missing a number or letter anywhere in it, or maybe not missing, but the wrong number/letter somewhere in the private key. That is a shitload of combinations to guess by yourself lol.

But is there is some program to crack those type of things if you know almost all of it? Trying different things until it matches your public key? I hope it does so I would get the relief that even if I screwed up one element, I will be able to recover my private key, and at the same time my savings.

Just need a convincing answer about such programs before I transfer them into that wallet.

Thanks
Yes extremely easy.
https://bitcointalk.org/index.php?topic=316979.0

Wow he found it quick!

Thanks, that's a relief.


Title: Re: Is it possible to brute-force a private key missing 1 number or letter?
Post by: Rannasha on December 08, 2013, 08:44:15 AM
If 1 symbol is missing in a 30-symbol string, the number of possible keys is 31 * 58 (31 for the number of spots the missing symbol could be, 58 is the number of different symbols in base58-encoding). That's 1798 possibilities. Not that many.


Title: Re: Is it possible to brute-force a private key missing 1 number or letter?
Post by: Abdussamad on December 08, 2013, 09:04:00 PM
Wow he found it quick!

Thanks, that's a relief.


This is bad advice. You said it yourself there are 50 characters and any one of them could be wrong. There is no way to bruteforce that.

I seriously suggest you give up on paper wallets for now. The way you are going about it you will loose your coins because you made a mistake and not because somebody stole them from you.


Title: Re: Is it possible to brute-force a private key missing 1 number or letter?
Post by: Talbot49 on December 08, 2013, 11:23:32 PM
Coins already sent  :-[

But the link user705 sent,https://bitcointalk.org/index.php?topic=316979.0,  he had a private key with 1 ellement missing, he didnt tell users where it was, he gave the public key to match and somebody find it really quick like a F in the middle.. So I think it that rare case I'll be able to get them.. Same process as brute forcing brainwallets with almost the good password.

Right?  ???