Ethereum Classic Suffers Yet Another ‘Large 51% Attack’ Just Days After Losing $5.7 Million
It hasn’t been even a week since Ethereum Classic suffered a 51% attack where the attacker got its hands on $5.7 million that the blockchain had yet another “large 51% attack.”
As reported by Bitfly, this attack has caused a reorganization of more than 4000 blocks.
The Twitter official page of Ethereum Classic asked all exchanges, mining pools, and other service providers to either substantially increase deposits and mining payouts or temporarily pause them all.
“ETC developers are working to find safe, and viable solutions,” it said.
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
“Even given its risk-averse culture, at this point making the jump seems lower-risk than not making it,” he said.
More details about this attack aren’t available yet, but the attack from last week only took 17.5 BTC worth $192k to acquire the hash power that allows the attacker to double-spend 807,260 ETC ($5.6 million) and further capture 13k ETC in block reward, as per Bitquery report.
“Nothing is 100% secure,” said Binance CEO Changpeng Zhao, adding, although bitcoin has a “super high degree of immutability,” even that is not 100%.
The first attack started on July 29 when the attacker withdrew 807k ETC from crypto exchanges and sent them to several wallets. The next day, the attacker started mining blocks by purchasing the hash power from Nicehash provider daggerhashimoto at double the price.
The attacker inserted the private transactions of sending money to his/her own wallets, to the blocks they were mining but didn’t publish the blocks as such, not noticed by anyone. The attacker then sent money back to the crypto exchange in small portions — the exchange here is believed to be OKEx, as “confirmed” by Victor Fang, CEO of Blockchain Ecosystem Intelligence Anchain.
On August 1st, the attacker published his/her blocks and executed the chain re-organization.
The price of the cryptocurrency, however, isn’t affected as it remains stable since the weekend's drop in line with Bitcoin and much of the crypto market and continues to trade above $7.