The alt-coin NXT has a big problem with this. They pretty much _only_ support brain wallets. The clients have these giant warnings if you use a pass-phrase shorter than 30 chars, but it still happens and a lot of new users get their money stolen 3 seconds after they get it. Some new clients use a real wallet, but that move can't come fast enough!
How to steal Bitcoins that are protected by weak passphrases
41–50 of 97 posts
Re: How to steal Bitcoins that are protected by weak passphrases
#42Conspiracy theory : Is directory.io phishing ? It is possible that people would try to find their private key on directory.io for fun. You can do that by jumping to the relevant page. Meanwhile, the servers at directory.io would cache the GET requests and blast through the handful of keys on that page. The site is likely generating the pages on the fly. You can type directory.io/ x : 904625697166532776746648320380374…
> The site is likely generating the pages on the fly.
The site is definitely generating hashes on the fly. There is not enough known storage in the universe for all possible 32 byte private keys. To be more precise, 1E77 is within a few orders-of-mag of the estimated number of atoms in the universe.
Re: How to steal Bitcoins that are protected by weak passphrases
#43Deterministically generating wallets is just dumb. It's the exact opposite of randomly generating wallets. We spend all this time on making things cryptographically secure and then mess it up by using a tiny subset of the keyspace. Why would anyone find this to be a good idea?
For some, P(losing key) > P(key theft)
P(key theft) is rather hard to calculate, given the entire universe is up against you and you have no visibility.
There are plenty of ways of avoiding losing a key, or generating pneumonics from secure keys.
Re: How to steal Bitcoins that are protected by weak passphrases
#44So... hunter2 is not ok?
Seven asterisks is a really shitty password.
Re: How to steal Bitcoins that are protected by weak passphrases
#45Earlier quoted context omitted.
The chance of that happening is so small it's not worth worrying about, ever. Your brain is not equipped to handle numbers on the scale of 2^-160.
I guess I've a better chance at lottery
You have a better chance of winning the lottery twice, getting struck by lightning three times, then getting snuffed out by a wayward meteor.
Re: How to steal Bitcoins that are protected by weak passphrases
#46I have spent quite a lot of time (~250h) on this problem as part of my dissertation and found ~18k brainwallets. Most of the 10k brainwallets found by the author have probably been made by another 'researcher' who is actively probing the network to look for thieves. There are many other similar analyses online which have better and more interesting results than this. Edit: I can upload some rather large and confusing…
I am interested :D
Here you go: http://i.imgur.com/XmOqvvW.jpg
I have a few more but they are even more confusing. Red nodes are brainwallets and blue nodes addresses that brainwallets transfer to. You will notice the massive cluster on the left, that is the 'researcher' who is actively probing the network.
The rest are standard brainwallet transactions and thefts.
The big red dot is a bug :P
Hope that was useful
Re: How to steal Bitcoins that are protected by weak passphrases
#47I'm really don't know much about the technical details of bitcoin, but why is a bitcoin address tied to a specific key pair? Why isn't the address+balance just signed with a key pair? That way me knowing a key pair wouldn't get me an address with a balance in it... is there something i'm missing? EDIT: I guess it doesn't matter, since the address space is so large. Either way, if i were targeting an account, i would…
An address is essentially just the public half of a key pair.
Re: How to steal Bitcoins that are protected by weak passphrases
#48Earlier quoted context omitted.
The chance of that happening is so small it's not worth worrying about, ever. Your brain is not equipped to handle numbers on the scale of 2^-160.
Indeed, that is way smaller than planks length: https://www.wolframalpha.com/input/?i=is+2^-160+smaller+than...
You can't compare 2^-160 with a number with a unit attached- it's meaningless. 2^-160 meters is smaller than the planck length, but 2^-160 isn't.
If your unit is "the volume of the observable universe" you get a pretty large volume (on a human scale, anyway): https://www.wolframalpha.com/input/?i=%282^-160%29+*+%28the+...
edit: oh, the units came from the grand-parent post to yours, but wouldn't the correct conversion be "2^-160 earth's surface-areas"? That's actually bigger than the planck area- but still stupid small.
https://www.wolframalpha.com/input/?i=%28The+surface+area+of...
Re: How to steal Bitcoins that are protected by weak passphrases
#49Earlier quoted context omitted.
Indeed, that is way smaller than planks length: https://www.wolframalpha.com/input/?i=is+2^-160+smaller+than...
You can't compare 2^-160 with a number with a unit attached- it's meaningless. 2^-160 meters is smaller than the planck length, but 2^-160 isn't. If your unit is "the volume of the observable universe" you get a pretty large volume (on a human scale, anyway): https://www.wolframalpha.com/input/?i=%282^-160%29+*+%28the+... edit: oh, the units came from the grand-parent post to yours, but wouldn't the correct conversio…
Good catch, I just mentally assigned meter unit to 2^-160.
Re: How to steal Bitcoins that are protected by weak passphrases
#50So, I've always had a bad feeling about brain wallets. They make me uncomfortable. The fact that some folks consider them more secure than a random private key is even more worrisome. There is the fear of an exploit of your computer, which is valid. It's very, very common. But, if your computer is exploited the exploiter could still obtain your brain wallet if you use it on that computer. Cold storage of your private keys, protected with a passphrase, on a couple of USB flash drives in two locations seems the obvious choice for safely protecting your cryptocurrency. Yes, there are still potential exploits. When you plug those drives into an exploited computer, you're potentially exposing yourself.
I think we need a lot more security awareness among the general population before Bitcoin becomes a mainstream thing. Right now, it's simply too dangerous to use Bitcoin with most people's security practices and their understanding of security.