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Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn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Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#271

Post by fidelramos »

misnome wrote: post #171
Jach wrote: post #151

Earlier quoted context omitted.

Last time I did some numbers, bank of america spent around $1bn per year in cybersecurity alone, and bitcoin mining energy cost about 10x that. For ensuring the security of a trustless worldwide monetary system, it's not that bad in comparison.

… unless your trustless worldwide monetary system wants to process more than seven transactions per second. I guess BoA probably handles a little more than that?

The energy expense of Bitcoin is dominated by its Proof-of-Work algorithm, the cost of processing transactions is negligible compared to that. And the PoW operates over the root of the last block's Merkle tree, which is a hash of all the transactions in the block. Being a fixed-size hash it doesn't matter if the block contains 1,000, 1 million or 1 billion transactions.

Therefore Bitcoin could scale to handle millions of transactions per second with a sublinear increase in electricity spent. [0]

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

Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#272

Post by GTP »

mrb wrote: post #136
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.

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…

It shouldn't be so easy to derive a private key from the corresponding public key. Is the attack you're referring to working because most of the bits of the private key are already known or am I missing something else here?

Re: Bitcoin puzzle #66 was solved: 6.6 BTC (~$400k) withdrawn

#273

Post by mandmandam »

killerstorm wrote: post #266
mandmandam wrote: post #247

Earlier quoted context omitted.

This attack wouldn't have worked in a mining free, fee-less cryptocurrency with sub-second confirmation times (ie, block lattice). The only reason we're still talking about BTC is bag-holders. It's vastly technologically inferior on every metric. Talking about BTC's failures as if they exemplify cryptocurrency is just like attacking solar panels on the basis of whale oil's flaws.

How is this "block lattice" secured?

Quite well, thank you! Coming up on nine years without hacks, and apparently quantum-resistant.

The next release of Nano (the original and best imo*) manages spam to the point where fee-less sub-second transactions can be maintained even while under a directed spam attack.

If you want to learn more there's plenty of documentation:

Overview: https://docs.nano.org/what-is-nano/overview/

More technical docs: https://docs.nano.org/#

* - I love how it was distributed, and the team are extremely focused on making it work at a "commercial grade" as opposed to working up hype.

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

#274

Post by shakiXBT »

GTP wrote: post #272
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…

It shouldn't be so easy to derive a private key from the corresponding public key. Is the attack you're referring to working because most of the bits of the private key are already known or am I missing something else here?

That's precisely what happened, knowing the public key of an address is commonplace (as long as the address has done at least one tx) and doesn't compromise the security of its private key

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

#275

Post by bhaak »

EGreg wrote: post #268
Powdering7082 wrote: post #86

Earlier quoted context omitted.

> there's no chance to stay safe when you put that kind of target on your back. Vitalik Buterin seems to be a counter example here, his net worth peaked around $1.46 billion. He has some interesting writing on how he stays secure. At one point the SHIBA token sent a huge amount of funds to his cold wallet and he details what he did to securely access those funds: https://decrypt.co/91000/ethereum-founder-vitalik-bute…

I recommend to everyone to take their 12 words, write em 3 times on a piece of paper, cut it into 9 pieces and hide them in places only you’d know

So nobody will be able to recover them if you are hit by a bus or develop dementia?

This problem is harder if you want to pass on your crypto after you can't use them anymore.

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

#276

Post by bhaak »

pcthrowaway wrote: post #233
pas wrote: post #131

Earlier quoted context omitted.

how would anything ever be immutable if people can reassign the symbol/pointer/name? the DAO hack happened, immutably, no one disputes it. the hashes and blocks and transactions are well-known. so there was a "schism", that explicitly validates the fact that without this large-scale cooperation, without the redefinition of what Ethereum is, it would be still be what is on that other branch. these both provide evidenc…

The version of Ethereum after the hack became known as Ethereum Classic. The Ethereum foundation decided to go with a fork of the chain prior to the hack, and pretty much all the devs and the community followed. The value of Ethereum is entirely derived from what people are willing to pay for it, and community is a big part of that. The version of Ethereum which underwent the attack didn't cease to exist, and people…

Small nitpick. In both chains the attack happened.

But in one chain the whole community decided to disown the attacker by injecting hard coded transactions that would send the Ethers back to their original owners.

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

#277

Post by BigParm »

fidelramos wrote: post #269
fidelramos wrote: post #260

Earlier quoted context omitted.

How could a bot/human steal the funds without knowing the private key? Edit: typo

Ok there is one good explanation for this case that I found in another comment here [0]: the person who found the private key made a transaction moving only part of the full reward, but in doing so exposed the full public key. A was monitoring the puzzle address for activity, picked up the public key, used it to crack the private key quickly and moved the rest of the funds. Fascinating that the original cracker would…

You can't derive an secp256k1 privkey from the associated pubkey. That's the whole point.

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

#279

Post by funnyfoobar »

mrb wrote: post #136
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.

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?

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

#280

Post by csomar »

fidelramos wrote: post #260
csomar wrote: post #220

Earlier quoted context omitted.

If the real puzzle solver didn't see this coming, he kinda does deserve it. Bitcoin blocks takes 10-20 minutes to confirm. This leaves enough time for a bot/human to take over. I am pretty sure he could have contacted a miner/pool and arranged a deal with them.

How could a bot/human steal the funds without knowing the private key? Edit: typo

I am not sure about this one but for the other puzzles, the solution is usually hashed and the submitter has to provide the solution in the Bitcoin script to solve for the hash. This disclose the solution (and thus the private key). This is not the case for signed Bitcoin transactions but these have special script functions. So if you don't use those, you lose these protections.
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