Bitcoin Protocol Vulnerability Could Lead To a Collapse

First time accepted submitter stanga writes "Cornell researchers unveiled an attack on the Bitcoin mining protocol that enables selfish mining pools to earn more than their fair share. In a technical report the authors explain this attack can be performed by a pool of any size. Rational miners will join this pool to increase their benefits, creating a snowball effect that may end up with a pool commanding a majority of the system's mining power. Such a pool would be able to single-handedly control the blockchain, violating the decentralized nature of the increasingly successful Bitcoin. The authors propose a patch to the protocol that would protect the system from selfish mining pools smaller than 25% of the system. They also show that Bitcoin can never be safe from selfish mining pools larger than 33% of the network, whereas it was previously believed that only groups larger than 50% of the network were a threat to the system. The question is — can the miners operating today adopt the suggested fix and dismantle too-large pools before a selfish mining pool arises?"

Comments

NBD

[hawkeyeMI]

This attack would be very, very difficult to achieve. Doesn't seem very worrying and I'm sure it'll be fixed well before it becomes an issue. There are already some pretty good discussions on /r/Bitcoin/ covering why it's not as big a deal as the sensational headline here makes it out to be.

Tinfoil hat

[guruevi]

So that's what the NSA datacenter is for...

Wow. A really really unethical headline...

[Anonymous Coward]

Someone trying to buy some bitcoins for cheap?

Here is the commentary from one of the Bitcoin core developers: https://bitcointalk.org/index.php?topic=324413.msg3476697#msg3476697

This is an old known attack which is boring, made a little more interesting by also assuming that the attacker has sybil attacked the network and inserted itself between every node. The result is that they can mine a disproportionally large share of coins. Academically interesting, but not terribly significant.

Mostly it's just another example that overly large pools are bad for the network, and that preventing sybil attacks (e.g. by miners setting up additional trusted peerings between each other) is useful.

Re:The Wild West

[93 Escort Wagon]

How can they be exciting? It already costs more in power bills than you make mining and you have to have specialist hardware (unless you're stealing cycles elsewhere or are a retard when it comes to money).

Parents are paying the electricity bills and buying the computers.