Share this article
Ethereum Classic Hit by Third 51% Attack in a Month
August has been an awful month for Ethereum Classic as the blockchain suffered yet another 51% attack.
By Zack Voell
Updated Sep 14, 2021, 9:49 a.m. Published Aug 29, 2020, 11:00 p.m.
Make us preferred on Google
The Ethereum Classic blockchain suffered a 51% attack Saturday evening, its third such attack this month, noticed by mining company Bitfly, which also spotted the first attack on Aug. 1.
STORY CONTINUES BELOW
Don't miss another story.Subscribe to the Crypto Daybook Americas Newsletter today. See all newsletters
- The attack reorganized over 7,000 blocks, or two days' worth of mining, according to a tweet shared by Bitfly. The first two attacks reorganized 3,693 and 4,000 blocks respectively.
- Notably, a leading organization behind the Ethereum Classic network, ETC Labs, announced its strategy to protect the network from additional attacks last week, including defensive mining that is intended to stabilize the network's plummeting hashrate and resist future 51% attacks.
- Stevan Lohja, technology coordinator at ETC Labs, in a private message with CoinDesk, said he finds the timing of the attack "very suspicious" as it came just a day after a meeting of Ethereum Classic core developers regarding "aggressive innovation" in the blockchain's proof of work.
- ETC Cooperative, another prominent foundation supporting the network's development, took to Twitter following Saturday's attack saying, "We are aware of today's attack and are working with others to test and evaluate proposed solutions as quickly as possible."
- After the first two attacks, exchange OKEx responded by saying it will consider delisting the asset due to the network's severe lack of security. Coinbase also took drastic measures by extending deposit and withdrawal confirmation times for ETC to roughly two weeks.
- Following the latest attack, leading cryptocurrency derivatives exchange FTX will reconsider its ETC perpetual futures contracts, according to CEO Sam Bankman-Fried in a private message to CoinDesk. He said this is so even though FTX doesn't support spot trading and the cryptocurrency network's insecurity has less of a direct effect on the risk of offering futures trading.
- The cryptocurrency seems largely unaffected by the series of attacks, trading at $6.86 at last check, less than 4% below its price during the second attack. The coin has traded hands between $6 and $8 for nearly the entire month of August.
UPDATE (Aug. 29, 23:03 UTC): Adding comment from ETC Cooperative.
UPDATE (Aug. 30, 01:05 UTC): Adding comment from ETC Labs' technology coordinator.
UPDATE (Aug. 31, 16:59 UTC): Clarifying Lohja's comment in reference to Ethereum Classic core developers, not "Ethereum Core" developers
More For You
KuCoin captured a record share of centralised exchange volume in 2025, with more than $1.25tn traded as its volumes grew faster than the wider crypto market.
What to know:
- KuCoin recorded over $1.25 trillion in total trading volume in 2025, equivalent to an average of roughly $114 billion per month, marking its strongest year on record.
- This performance translated into an all-time high share of centralised exchange volume, as KuCoin’s activity expanded faster than aggregate CEX volumes, which slowed during periods of lower market volatility.
- Spot and derivatives volumes were evenly split, each exceeding $500 billion for the year, signalling broad-based usage rather than reliance on a single product line.
- Altcoins accounted for the majority of trading activity, reinforcing KuCoin’s role as a primary liquidity venue beyond BTC and ETH at a time when majors saw more muted turnover.
- Even as overall crypto volumes softened mid-year, KuCoin maintained elevated baseline activity, indicating structurally higher user engagement rather than short-lived volume spikes.
More For You
How a 'perpetual’ stock trick could solve Michael Saylor’s $8 billion debt problem
The bitcoin treasury firm is using perpetual preferreds to retire convertibles, offering a potential framework for managing long-dated leverage.
What to know:
- Strive upsized its SATA follow on offering beyond $150 million, pricing the perpetual preferred at $90.
- The structure offers a blueprint for replacing fixed maturity convertibles with perpetual equity capital that removes refinancing risk.
- Strategy has a $3 billion convertible tranche due in June 2028 with a $672.40 conversion price, which could be addressed using a similar preferred equity approach.
Top Stories
