6 ms·
Contest: Hack my bitcoins and keep them
- graemeism 14y agoFantastic idea actually. Comments on this page are fascinating. This too: "The fourth address was robbed in 7 hours"..."I did not tell anyone about my test"! LOL, nuts.
- arkitaip 14y agoBasically people scan brainwallets for weak passwords. Kinda obvious but still food for thought.
- smokeyj 14y agoI wonder what the best convention for generating secure brainwallets is. They seem much more prone to dictionary attacks if you're not careful. Is inventing words and nonsensical phrases the norm?
- nwh 14y agoUsing a brain wallet in any form is reckless. You're better off storing your private key on paper or using SSSS[0]. [0]: http://point-at-infinity.org/ssss/ http://point-at-infinity.org/ssss/
- patrikr 14y agoWell, for one thing, don't use just one round of SHA-256. Or more generally: don't use the same algorithm as everyone else. Chain together different hash functions, and/or run them more than once.
- w-ll 14y agoI actually modified a Bitcoin address tool to generate brain wallets in python specifically for brute forcing week brains. https://github.com/willwharton/pybrainwallet https://github.com/willwharton/pybrainwallet
- deleted 14y ago[deleted]
- unimpressive 14y agoWrong thread.
- moxie 14y agoFor generating memorable passphrases with high entropy, I like the "diceware" system: http://world.std.com/~reinhold/diceware.html http://world.std.com/~reinhold/diceware.html Use it to generate the one password that you use for unlocking your password manager, where all of your randomly generated passwords are kept. Since most people don't do that, this post makes me think that my idle CloudCracker cycles spent mining BTC would actually be better spent mining brainwallets. =)
- daniel-cussen 14y agoFunny, I made one of these with D&D dice. Is it considered crypto-kosher?
- funkdobiest 14y agoI thought you meant Andrew "Dice" Clay so that it makes a phrase like Hickory Dickory Dock...
- brownbat 14y agoIt's like a nano X Prize, seemingly aimed against pass phrases. Bitcoin wallet hacking is a really fun test case, because it begs people to acknowledge the opportunity costs involved in cracking. Cracking a wallet password can always be baselined against mining. Cracks should happen whenever: operations_per_password / wallet_size < operations_per_coin (You can increase security either by growing your passwords or shrinking your wallets. There's some ideal inflection point in there somewhere...) There are opportunity costs to cracking passwords in all other scenarios too, they're just harder to observe. ie, whenever it's cheaper to bribe one of your employees than crack their password, then, congrats, your passwords are officially "secure" (even if your business isn't).
- linhares 14y agothis is not cracking, the guy has brainwallets and told all the clues to get into to them.
- Xcelerate 14y agoDang it, I was hoping this didn't make it on HN :) I've been working on this for a few days! Currently I'm porting SHA256, RIPEMD160, and ECDSA key pair generation to CUDA. ECDSA is giving me some trouble though...
- lucaspiller 14y agoNice work, and good luck!
- mrb 14y agoWhy Nvidia (CUDA)? It it the only hardware you have access to? If you have access to AMD graphics cards, you should have written your code in OpenCL to target this hardware. Nvidia cards are a lot slower per $ and per Watt than AMD ones when running SHA256/RIPEMD160/ECDSA. That is why vanitygen was done in OpenCL.
- Xcelerate 14y ago> Why Nvidia (CUDA)? It it the only hardware you have access to? Yep. Also, learning CUDA would be a benefit for my graduate research, so it's not a complete loss :)
- eksith 14y agoIf you'd like to use a mnemonic (a nice long sentence) but need some extra gibberish to prevent it being easily guessed, you can try this : http://eksith.com/experiments/passwordencoder/ http://eksith.com/experiments/passwordencoder/ Basically takes the first letter of every word in your sentence and adds its position in the alphabet (plus rotate if you like). If the sentence you choose is sufficiently unique, the password will also be harder to crack.
- beala 14y agoSince the last half of the password is partially determined by the first half, this doesn't add much additional entropy (an attacker only has to guess your phrase, and which options you've selected). In practice this may help in a security through obscurity way, but now your method is public.
- eksith 14y agoIt's been public since 2008 :) This may work better for me since I've used phrases from out-of-print books and some are latinized phrases in Sinhalese. I prefer to use random passwords that I can add to a master file that's PGP encrypted, but in the absence of that, I can tailor this to a site and add character rotation.
- cbr 14y agophrases from out-of-print books Less secure now that there's massive book scanning going on.
- zobzu 14y agoopenssl rand -base64 50 ;-)
- gojomo 14y agoThere are many ways such little cash bonuses can be left 'in the blockchain' for people to discover. Imagine a video/podcast which offers various obscured glimpses of a private key's QR code... the first viewer to freeze-frame and stitch-together collects the prize. Or imagine any other riddles/puzzles with a solution space resistant to brute-force search. The prize for the first solver can be left in the blockchain, with a private key derived from the solution. After 'easter eggs' (in real life or software), these could be called 'eggcoins'. (I find a prior use of that term related to a geocached souvenir coin.)
- mrb 14y agoOne more private address was just brute-forced, and coins were moved: https://blockchain.info/address/1ECM1W1ZWtWDvTm3yWYWJA9mKn4Dwaaz1o https://blockchain.info/address/1ECM1W1ZWtWDvTm3yWYWJA9mKn4D... 3 out of 5 remain to be found :)
- wereHamster 14y agoIf you follow best practice and generate a new address for each tranaction, brainwallets don't scale. At least not until https://en.bitcoin.it/wiki/BIP_0032 https://en.bitcoin.it/wiki/BIP_0032 is implemented. One bitcoin is a lot of money (about $40). He created five wallets, so he's giving away $200. That's not a trivial amount of money for such a test.
- joelthelion 14y agoIt's not a "best practice", it's only something you should to if you want to remain as anonymous as possible. It's perfectly acceptable to use only one address if you don't care much about anonymity.
- jcoder 14y ago"Hack my bitcoins and keep them" So, everyone with bitcoins is always running this contest?
- shared4you 14y agoFINAL ANSWER: http://linja-aho.blogspot.fi/2013/03/bitcoin-brain-wallet-cracking-contest.html http://linja-aho.blogspot.fi/2013/03/bitcoin-brain-wallet-cr...