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Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn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Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#161

Post by [deleted] »

Dibby053 wrote: post #155
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…

That must hurt. In case I crack the next puzzle... how should I go about collecting the prize without having to mine a block myself or trust a miner not to screw me over?

[deleted]

Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#162

Post by ChrisClark »

Stagnant wrote: post #146
ChrisClark wrote: post #139

Earlier quoted context omitted.

Edit: I see it's because I'm this instance there was less entropy, I guess a normal transaction has a lot more bits to guess Why doesn't this happen with every large transaction then? Someone tries to move 10 BTC, instantly stolen? Basically you're saying that every single Bitcoin transaction can be stolen "really fast". Am I missing a step here?

It is based on the fact that the upper range limit of the private key used in the puzzle is known. A securely generated private key would not be vulnerable even if its public key is known. The second post on this thread[0] has a helpful chart that makes it easier to understand. 0: https://bitcointalk.org/index.php?topic=5218972.0

Thanks

Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#163

Post by mrb »

Dibby053 wrote: post #155
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…

That must hurt. In case I crack the next puzzle... how should I go about collecting the prize without having to mine a block myself or trust a miner not to screw me over?

To avoid this risk: either you solo mine your transaction, or you submit your transaction to a mining pool that will not broadcast it to the P2P network until it is mined. Some pools offer this as a service (eg. https://slipstream.mara.com/). This is kludgey but this is because the puzzle is inherently limited by its technical design.

Note that this issue doesn't exist with puzzle numbers that are multiple of 5, because these addresses have their public key already known. So everyone is on a level playing field. The multiple of 5 have been solved up to #125: https://privatekeys.pw/puzzles/bitcoin-puzzle-tx

Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#164

Post by nkrisc »

hoerzu wrote: post #153
fernandopj wrote: post #148

Earlier quoted context omitted.

But how could he have avoided this attack? I'm only familiar with Bitcoin's blockchain on a begginner level. But I assume the only way would be to avoid revealing the answer key (public) when sending the transaction to get the reward?

Private mempool transaction

I’m a relatively smart person, probably above average, but glad bitcoin hasn’t taken over banking because I don’t understand any of this.

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

#165

Post by drexlspivey »

thrtythreeforty wrote: post #149
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…

What is the less-naive way to claim this type of puzzle?

https://slipstream.mara.com/

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

#166

Post by cmcaleer »

londons_explore wrote: post #37
Dwedit wrote: post #26

Do they have a buyer for that $400k? If not, it's not worth $400K.

400k I think is no problem. I heard of someone with 10,000 BTC having some serious trouble finding a buyer though.

I can't imagine that getting that filled OTC reasonably close to the mark would be serious trouble. Germany managed to sell 50,000 BTC without much trouble a few months ago.

Then again, it may be serious trouble if you have serious issues explaining the source.

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

#167

Post by drexlspivey »

mrb wrote: post #163
Dibby053 wrote: post #155

Earlier quoted context omitted.

That must hurt. In case I crack the next puzzle... how should I go about collecting the prize without having to mine a block myself or trust a miner not to screw me over?

To avoid this risk: either you solo mine your transaction, or you submit your transaction to a mining pool that will not broadcast it to the P2P network until it is mined. Some pools offer this as a service (eg. https://slipstream.mara.com/ ). This is kludgey but this is because the puzzle is inherently limited by its technical design. Note that this issue doesn't exist with puzzle numbers that are multiple of 5, bec…

There is also another puzzle for finding a sha256 collision, the address script just checks if the 2 inputs are different but have the same hash and if true it unlocks the coins.

That one is even easier to steal because it doesn't even require a digital signature and there are tons of bots out there inspecting live transactions and if they don't require a signature they just create a new transaction with an increased fee and their own address as recipient.

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

#170

Post by thrtythreeforty »

drexlspivey wrote: post #165
thrtythreeforty wrote: post #149

Earlier quoted context omitted.

What is the less-naive way to claim this type of puzzle?

https://slipstream.mara.com/

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