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Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

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Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#321

Post by rtkwe »

the_clarence wrote: post #286
mrb wrote: post #136

Earlier quoted context omitted.

No private key was posted too early. What happened is the person who spent all the computing power to brute force the 66 bits broadcasted, naively, a transaction to send the 6.6 BTC reward to his wallet. However, when doing so, the public key is by design revealed on the blockchain. Someone's bot whose sole purpose is to steal this puzzles rewards was monitoring the blockchain and spotted the transaction before it go…

You need 2^65 operations so this is likely not what happened. What you're thinking about is the birthday attack that only works to find collisions and not to find a specific "pre-image"

No knowing the public key reduces the number of keys you have to attempt to find the corresponding private key. If it required the same number of attempts they would have just found it first without having to wait for the broadcast to snipe it.

https://en.wikipedia.org/wiki/Pollard%27s_rho_algorithm_for_...

Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#322

Post by rtkwe »

funnyfoobar wrote: post #279
mrb wrote: post #136

Earlier quoted context omitted.

No private key was posted too early. What happened is the person who spent all the computing power to brute force the 66 bits broadcasted, naively, a transaction to send the 6.6 BTC reward to his wallet. However, when doing so, the public key is by design revealed on the blockchain. Someone's bot whose sole purpose is to steal this puzzles rewards was monitoring the blockchain and spotted the transaction before it go…

noob here: but are not the public keys anyway available on block chain? that means literally every thing can be brute forced?

The puzzles have a set number of unknown bits smaller than the total key length making them more vulnerable to these attacks. For true unknown keys the reduction in your search space doesn't bring it down into the range where it's computationally possible to do.

Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#323

Post by DoctorOetker »

drexlspivey wrote: post #180
thrtythreeforty wrote: post #170

Earlier quoted context omitted.

Aren't you effectively trusting that service not to front run you?

Yes, the only other way is to mine it yourself. They are a public company that run their own miners if it makes you feel any better.

No, the other way would be for the organizer to author proper scripts that prevent front-running.

Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#324

Post by DoctorOetker »

dools wrote: post #132
arcanemachiner wrote: post #90

Looks like the coins were stolen by a bot: > https://bitcointalk.org/index.php?topic=1306983.msg64535839#... I'm not super familiar with the concept (and I'm too lazy to look into it TBH), but I think the would-be winner posted the private key before enough (any?) blocks were mined, and the thief posted a transaction with a bigger fee, and the thief's transaction was in the block that got mined.

So someone stole the prize and left some sort of calling card mocking everyone solving bitcoin puzzles? 1Jvv4yWkE9MhbuwGU66666666669sugEF 0.00000001 1YouAreSoDumbLoL666666666667K5aR4 0.00000002 1WhatWereUThinking6666666662wkqq1 0.00000003 1YouDeserveNothing6666666665sbbBC 0.00000004 1YouEpicFaiLure66666666666688GSDA 0.00000005 1BitchAssLoser66666666666669dBUVg 0.00000006 1AndEveryoneELse666666666669Vnc8C 0.00000007 1…

from the peanut gallery it is impossible to differentiate organizer vs thief, the organizer did invest the money to host the prize, but not the critical thinking to organize a convincing prize?

Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#325

Post by mistrial9 »

rsynnott wrote: post #248
mistrial9 wrote: post #192

Earlier quoted context omitted.

yes, in California, City of Albany, Target store near San Francisco, refused to take cash at the checkout not long ago.

Was this refusal of a normal cash transaction, or something silly (unreasonably large transaction/transaction all in one cent coins/transaction which would raise money laundering alarms etc)? Like, if you try to pay 10,000 dollars in cash, or, say, buy a stack of prepaid debit cards with cash, most places are going to be sceptical of that.

a small shopping trip with ordinary items totaling less than thirty dollars, actually. Many places of various kinds in California are not accepting cash today - San Francisco passed local law to require accepting cash as one result.

Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#326

Post by michaelmior »

GTP wrote: post #257
beepbooptheory wrote: post #128

Earlier quoted context omitted.

Each key is a brand in the analogy.

Why should the analogy consider each key as a different brand of lock? Each key needs to be cracked separately, but you can use the same method for all of them (assuming one finds a general method and not one based on some property that only a subset of the keys has). So it should be akin to locks of the same brand, using different keys to open them. But that, being of the same brand, can be picked in the same way.

Perhaps each key is not a different brand, but given that the puzzle had only 66 known bits, it seems equivalent to knowing what some of the cuts are on a physical key.

Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#327

Post by fidelramos »

GTP wrote: post #319
fidelramos wrote: post #301

Earlier quoted context omitted.

I agree with part of what you say but not with the implication. Yes, Bitcoin Cash [0] is the Bitcoin that chose to scale on-chain. The split happened in 2017 and since then it has decreased in price both compared to BTC and USD. What I strongly disagree with is that a Bitcoin with bigger blocks and hence larger transaction capacity is inherently less valuable. That is an unfair comparison because Bitcoin Cash, when t…

I didn't say that having larger blocks makes a crypocurrency hinerently less valuable, my point was that it's not enough to obtain the widespread adoption and the consequent increase in value you were talking about. But I also see your point on having those improvements baked in BTC at the right moment vs having a new crypocurrency. But afaik Ethereum is able to handle many more payments than BTC (not sure if transac…

Blockchain scalability while keeping decentralization is now a solved problem, you can research how sharding is implemented in cryptocurrencies such as XTZ or EGLD, or read this rationale [0] for terabyte blocks in Bitcoin Cash. Why do blockchains such as BTC or ETH refuse to scale on-chain then? That's a separate debate, but I believe there are vested interests in them not scaling.

Regarding volatility I agree that it's currently an issue, but not an insurmountable problem in my opinion:

1. Payment gateways can offer automatic asset conversion to minimize volatility risk for payment takers. This means I could pay in whichever cryptocurrency the payment gateway would take and the receiver would get whatever currency they have set up in their account. They might want to keep some currencies and convert others, so the payment gateway could offer an option to decide that, and in which amounts (e.g. "keep 10% of each BTC payment, convert the rest to USD").

2. Price volatility should reduce as a cryptocurrency is more widely used. In the alternate universe where BTC scaled to be larger than all credit card networks combined its price could be more stable than many fiat currencies.

[0] https://blog.vermorel.com/journal/2017/12/17/terabyte-blocks...

Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#328

Post by mannyv »

arcanemachiner wrote: post #90

Looks like the coins were stolen by a bot: > https://bitcointalk.org/index.php?topic=1306983.msg64535839#... I'm not super familiar with the concept (and I'm too lazy to look into it TBH), but I think the would-be winner posted the private key before enough (any?) blocks were mined, and the thief posted a transaction with a bigger fee, and the thief's transaction was in the block that got mined.

So how do you test your generated key? You can't just go and submit lots of transactions. That would presumably be expensive.

Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#329

Post by fernandopj »

loopdoend wrote: post #232
sourraspberry wrote: post #224

Earlier quoted context omitted.

Isn't this a bit insane? Does this not imply the entire Bitcoin protocol is fundamentally flawed?

No because it is not normal to have such low entropy for private keys. It wasn't designed with these puzzles in mind, nor should it be.

Your reply and Jerrrrrrry's closed this understanding for me.

The attack itself can't be mitigated because there's the incentive to try to force the blockchain with your own theft block because your fee is much higher for what appears to be the same transaction. But this attack, like you said, is only feasible for this niche domain of low entropy private keys.

Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#330

Post by AnotherGoodName »

GTP wrote: post #256
arcastroe wrote: post #200

Earlier quoted context omitted.

the problem of finding discrete logarithms is the same problem as breaking elliptic curve cryptography.

Technically, while the two problems share the same name, the one on elliptic curves is matematically different from the one over finite fields modulo a prime number.

I politely don’t understand this. It’s taught in cryptography 101 that breaking ecc is just solving the discrete logarithm problem and there’s a ton of online articles about how to break ecc if you’ve solved the discrete logarithm problem (not that anyone has).
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