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Large Bitcoin Collider Is Generating Trillions of Keys and Breaking into Wallets

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Re: Large Bitcoin Collider Is Generating Trillions of Keys and Breaking into Wallets

#31

Post by pavel_lishin »

bigtimeidiot wrote: post #30
domador wrote: post #20

If this kind of attack is feasible, then maybe one should have several wallets and spread one's Bitcoin funds among these wallets, to dilute the risk. Maybe one wallet could be used just for receiving external transactions, but its funds could be immediately transferred to other wallets. Or maybe there are also weaknesses to this approach... I'm not currently a Bitcoin user, and ambivalent about Bitcoin's virtue, but…

> then maybe one should have several wallets and spread one's Bitcoin funds among these wallets, to dilute the risk Sounds like Bitcoin is ready for the mainstream!

To be fair, aren't bank accounts only insured by the government for up to $250,000 per account?

Re: Large Bitcoin Collider Is Generating Trillions of Keys and Breaking into Wallets

#32

Post by Animats »

About 10% of Bitcoins were created early, before 2012, and have never been traded. If somebody ever finds the key of the early lost Bitcoins, they'll have a huge payoff, over a billion dollars. Speculation is that either "Satoshi Nakamoto", whoever he is, is holding onto them for a big payoff, or somebody lost the private key for all those early Bitcoins. As the years go on, the second explanation seems more likely.

Re: Large Bitcoin Collider Is Generating Trillions of Keys and Breaking into Wallets

#33

Post by ryan-c »

xseven wrote: post #17
SomeStupidPoint wrote: post #13

Earlier quoted context omitted.

Small note, but 3,000 trillion is 3 quadrillion, not 3 quintillion. Which is their total, over a significant amount of time. The bitcoin network does over 3 quintillion (>3,000,000 trillion) hashes a second. So even if they were doing a significantly harder to compute hash -- they're still only a very small part of the computational power the bitcoin network is using. So it's probably already more effective to attack…

Multi-sig is the cure :)

P2SH addresses can be brute forced several orders of magnitude faster than P2PKH. The attacker needs to generate 1-of-2 multisig scripts in the following form:

OP_1 [compressed pubkey] [0x02, 29 random bytes, 3 byte counter] OP_2 OP_CHECKMULTISIG

A new compressed pubkey must be generated every 2^24 iterations.

You compute a sha256 midstate from the first 64 bytes, then restore and compute over the rest of the script for each subsequent iteration, then ripemd160 the output. Very easy to GPU accelerate.

The slowest part of address generation is the elliptic curve math, and this avoids it entirely for most iterations, only needing to to refresh the public key when the counter rolls over.

Re: Large Bitcoin Collider Is Generating Trillions of Keys and Breaking into Wallets

#34

Post by [deleted] »

xseven wrote: post #17
SomeStupidPoint wrote: post #13

Earlier quoted context omitted.

Small note, but 3,000 trillion is 3 quadrillion, not 3 quintillion. Which is their total, over a significant amount of time. The bitcoin network does over 3 quintillion (>3,000,000 trillion) hashes a second. So even if they were doing a significantly harder to compute hash -- they're still only a very small part of the computational power the bitcoin network is using. So it's probably already more effective to attack…

Multi-sig is the cure :)

[deleted]

Re: Large Bitcoin Collider Is Generating Trillions of Keys and Breaking into Wallets

#35

Post by m-j-fox »

xseven wrote: post #17
SomeStupidPoint wrote: post #13

Earlier quoted context omitted.

Small note, but 3,000 trillion is 3 quadrillion, not 3 quintillion. Which is their total, over a significant amount of time. The bitcoin network does over 3 quintillion (>3,000,000 trillion) hashes a second. So even if they were doing a significantly harder to compute hash -- they're still only a very small part of the computational power the bitcoin network is using. So it's probably already more effective to attack…

Multi-sig is the cure :)

Oh hi bitgo.

Re: Large Bitcoin Collider Is Generating Trillions of Keys and Breaking into Wallets

#36

Post by ryan-c »

SomeStupidPoint wrote: post #13
Bedon292 wrote: post #2

Very interesting work. 3 Quintillion keys generated, 3 private keys with coin in them. I have to wonder what processing power is being put into it, and if that power would be more effective at just mining coin, if someone were just after the money. At least in the short term. I think in the long term attacks like this might become more and more prevalent. Because at some point it may be easier to do this than mine ne…

Small note, but 3,000 trillion is 3 quadrillion, not 3 quintillion. Which is their total, over a significant amount of time. The bitcoin network does over 3 quintillion (>3,000,000 trillion) hashes a second. So even if they were doing a significantly harder to compute hash -- they're still only a very small part of the computational power the bitcoin network is using. So it's probably already more effective to attack…

The wallets they've found most likely were made with weak keys on purpose.

Re: Large Bitcoin Collider Is Generating Trillions of Keys and Breaking into Wallets

#37

Post by salesguy222 »

pavel_lishin wrote: post #31
bigtimeidiot wrote: post #30

Earlier quoted context omitted.

> then maybe one should have several wallets and spread one's Bitcoin funds among these wallets, to dilute the risk Sounds like Bitcoin is ready for the mainstream!

To be fair, aren't bank accounts only insured by the government for up to $250,000 per account?

To make matters worse, they're only insured to 250k in the event of a bank failure (running out of money)

having your account or identity hacked, on the other hand, you are on your own to make sure the bank replenishes your account ^.^

Re: Large Bitcoin Collider Is Generating Trillions of Keys and Breaking into Wallets

#38

Post by ryan-c »

SomeStupidPoint wrote: post #21
csomar wrote: post #18

Earlier quoted context omitted.

> So it's probably already more effective to attack wallets than join a mining pool. That's not how you make the calculations. The reason the idea was called stupid is because the math doesn't add up. My guess is that these 3 private keys had weaknesses in them. Even the probability that they were found by "luck" is way far off. Given merge mining is possible, I'd assume with some tweaking side-colliding + mining is…

I'm sorry, I'm not sure I understand your point: are you saying my math is off, given the claims of the article (ie, hashes computed, time spent, and compromises), or that the article is wrong because it's not that easy to crack? Google found a SHA-1 collision (160 bit hash, same size but different method) in 9 quintillion hashes (plus some crypto work). The article claims they found a collision against 3 of millions…

They're running a brute force preimage attack against all bitcoin addresses which currently have a balance. The reason they say "collision" is that if they found a key that hadn't been made weak on purpose, it would probably be a different key from the original (bitcoin addresses do not map 1-to-1 with keys).

Re: Large Bitcoin Collider Is Generating Trillions of Keys and Breaking into Wallets

#39

Post by ryan-c »

awirth wrote: post #24
alphydan wrote: post #10

Earlier quoted context omitted.

This explains the approach in more detail: https://lbc.cryptoguru.org/man/theory

This is confusing to me. The link describes narrowing the search space to ~136.17bit, but that is still far too large to be tractable. Do they get an additional birthday bound on that somehow? 68 bits would not be insane, but I don't really understand what's going on here. I highly doubt they found a collision with a probability of 2^-136, unless they exploited some kind of bad RNG bug (in which case the probability…

No birthday bound. The keyspace reduction is based on the number of addresses with a balance.

Re: Large Bitcoin Collider Is Generating Trillions of Keys and Breaking into Wallets

#40

Post by ZirconCode »

Animats wrote: post #32

About 10% of Bitcoins were created early, before 2012, and have never been traded. If somebody ever finds the key of the early lost Bitcoins, they'll have a huge payoff, over a billion dollars. Speculation is that either "Satoshi Nakamoto", whoever he is, is holding onto them for a big payoff, or somebody lost the private key for all those early Bitcoins. As the years go on, the second explanation seems more likely.

Or he didn't loose it and isn't motivated by money. Which seems also likely since he had the skills and decided not to cash in on the fame either.
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