Possible Double-Spend attack on BCash using Bitcoin Mining pool

Xynerise

sr. member

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Quote from: markblundeberg on February 16, 2018, 02:36:35 AM

The attack described is literally the definition of a 51% attack (https://en.bitcoin.it/wiki/Majority_attack). I don't understand why he relabels it as "withholding blocks".

To be fair, a 51% attack works by "withholding blocks" AKA private mining. It obviously won't work if the attacker broadcasts the blocks as he finds them.

markblundeberg

newbie

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The attack described is literally the definition of a 51% attack (https://en.bitcoin.it/wiki/Majority_attack). I don't understand why he relabels it as "withholding blocks".

monsterer2

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Quote from: Colorblind on February 13, 2018, 04:05:08 AM

This is very interesting attack vector on currencies that utilize same POW algo. (In this case contributing fraction of Bitcoin hash power can totally screw Bitcoin Cash, allowing double spend).

https://youtu.be/_cuImsvmSf4

Thoughts?

Yes, this is a common attack vector for new coins using the same hashing algorithm as established players. Basically, this is "do not do" no. 1 in the rules of PoW.

Colorblind

member

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This text is irrelevant

Quote from: ICOgenius on February 13, 2018, 04:56:01 AM

I have been spreading this video myself to anyone and everyone that will watch or those who even just may. Keep up the great work! The world must be informed of this possible danger! Embarrassed

That's actually very interesting attack vector, that does not point at Bitcoin directly but rather utilizes it's overpowering hash rate to screw any coin with same mining algo. BCH is obvious high profile target but I think number of smaller coins can be subjected to this kind of attack as well (and entry requirements will be orders of magnitude less).

ICOgenius