Child abuse imagery found within Bitcoin's blockchain | Hacker News Reader

Child abuse imagery found within Bitcoin's blockchain

theguardian.com

66 pointsasymmetric15 comments

A miner who knows where in the chain these files are could zero out the bytes, retaining just the hash of that area. Normal operation on the blockchain could continue, except that the miner wouldn't be able to validate any new transaction trying to spend the output that contains the illegal content. This doesn't feel like a loss anyone is going to worry about. The only affected parties would be the parties who put the data there, and presumably they aren't going to reveal themselves.

In other words, Bitcoin operation can continue with pretty much a non-controversial software change that allows miners to choose to ignore particular outputs.

If a miner genuinely doesn't know where in the chain these files are, then I'm not sure it can be claimed that the miner is in "possession" of it and the legal principle of mens rea will mean that the miner won't be criminally culpable in most jurisdictions.

And no one had seen it coming? It's way better than bittorrent trackers, it requires many many people to agree that something needs to be removed, but adding any data to publicly held records is very cheap, so those that uploaded pictures can do it again.

How are they storing this? I understand the links, there is enough bits to do that, but an image stored on-chain? How?

Over several transactions and you need to put it together, or will there be enough space to store an image in a OP_RETURN script?

83 bytes doesn't sound like it's enough to store any abuse image.

Here's an article which describes how to store data in the blockchain, along with some interesting (legal/SFW) examples:

http://www.righto.com/2014/02/ascii-bernanke-wikileaks-photo...

Haha, we can all see where this is going

“Only miners need the whole blockchain, and the blockchain contains illegal data, therefore mining is equivalent to possession and distribution of child porn...”

This is bad. Like, really bad. That "feature" of bitcoin has added more complications to the network than it is worth, IMO. Either the law's gotta change, or miners are going to start being prosecuted.

... or, the bitcoin developers will just have to add a way of removing that data when a new block is mined, which I guess is what will eventually happen. What a mess.

> That "feature" of bitcoin has added more complications to the network than it is worth, IMO

As long as there is any option of storing anything user-derived in the blockchain, this problem will exist. And it is conceivable that the transaction amount can be used to encode binary data... and this doesn't just impact Bitcoin, but also normal banks. Assuming a bank with two accounts and no transfer fees, I could transfer money between the accounts and encode my data e.g. in the "cent" division, with every transaction encoding a single byte. So technically the bank is in possession of child porn (or, to choose something of lesser importance, the tiny libdvdcss code), but is simultaneously not allowed to erase it due to financial transparency laws...

however if you don't tell them how you encoded it, nobody would ever know. the same way it would be possible to find something that could be considered illegal by searching the right way in any large enough [random] data. so where's the barrier?

Isn't the whole point of the blockchain that once something is there, there's no way to get rid of it (without invalidating the entire thing)?

Personally, I wouldn't say that was the whole point of it.

As far as I know (and that ain't much -- I'm not an expert), bitcoin's fundamental contribution was solving "The Byzantine Generals' Problem"[0] in a novel way by using its proof-of-work algorithm combined with the blockchain. This is how/why it works and has been adopted the world over.

Personally, I would say that the whole point of it was not to store censorship-resistant information, but to provide a store of value independent of the current system of state-controlled and/or -regulated fiat currency. The fact that it is also useful for storing censorship-resistant information is a side-effect of the developer adding that feature to the code.

[0]https://bitcointalk.org/oldSiteFiles/byzantine.html

This would appear to mean that the 12,500-ish people running a full Bitcoin node have child pornography on their machines. As do those with full nodes that haven't been active in the last 24 hours.

... that they can't easily remove.

You can easily remove it by ditching your full Bitcoin node. Of course, you can't really do that if you're doing some sort of business that relies on it.

Apparently there's leaked classified material in there too.

Well, that's a fiasco...

Price fall in 3..2..

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