- Ethereum Classic was just hit by a second 51% attack in the past six days.
- The first attack, which took place on August 1st, double-spent over $5.6 million in ETC.
- The damage caused by the second attack, which took place this morning, remains unknown for now.
Less than a week ago, on August 1st, Ethereum Classic (ETC) got hit by a 51% attack. A report by a blockchain data firm Bitquery suggests that the attack resulted in a double-spending of 807,260 ETC. According to the coin’s price at the time, this amount was worth $5.6 million.
However, this was only the beginning of ETC’s troubles, as the project just suffered its second 51% attack this week.
Ethereum Classic Suffers a Second 51% Attack
Only hours ago, Ethereum Classic was hit again, and this attack was reported by Ethermine mining pool’s parent firm, Bitfly. The report does not reveal much, apart from the fact that the attack took place in the early hours of Thursday morning.
Today another large 51% attack occurred on the #ETC which caused a reorganization of over 4000 blocks. Until further notice ETC pool payouts are disabled and we encourage all our miners to switch to our #ETH pool at https://t.co/f8Px6gGJiM in the meantime.
— Bitfly (@etherchain_org) August 6, 2020
According to the leading crypto exchange, Binance, over 4,000 ETC blocks got reorganized during the attack. Due to the incident, both Binance and Bitfly decided to stop all ETC transactions, including deposits, withdrawals, and payouts.
A new chain reorg of 4,000+ blocks has occurred on @eth_classic $ETC at block 10935622.
Our alert system caught this immediately and automatically halted withdrawals and deposits.
It appears to be a follow up 51% attack.
We will update you as things unfold.
— Binance (@binance) August 6, 2020
However, there was no mention of how much was double spent this time. The value of the attack, or rather, the damage it has caused, has yet to be determined.
How Does the 51% Attack Work and What Does it Do?
As many likely know, 51% attacks revolve around the reorganization of blockchain. It takes place when a group of blockchain miners manages to take over control of more than 50% of the network’s total hash rate.
Doing this allows the invaders to do almost anything, such as prevent transactions from being confirmed, or stop payments between users. They can even reverse transactions that already took place, and use the same coins for the second time.
This is, of course, rather difficult to achieve, especially with major coins like Bitcoin, which have massive networks that are next to impossible to hijack. Ethereum Classic, however, is far from this level, as proven by these two attacks.
The project will have to come up with a change that will prevent something like this from happening again, and Ethereum’s co-founder, Vitalik Buterin, suggested moving to a PoS consensus algorithm.
ETC should just switch to proof of stake. Even given its risk-averse culture, at this point making the jump seems lower-risk than not making it.
— vitalik.eth (@VitalikButerin) August 6, 2020
This would make sense, as ETC currently uses Proof of Work, which is considered outdated and risky.
