Ethereum Classic Suffers Another 51% Attack

Ethereum Classic has suffered another 51 percent attack this morning, resulting in the reorganization of over 4,000 blocks.

The attacker can reorganize the chains on a decentralized network when they gain over 51 percent of the total Hash Rate Hash Rate A hash rate is the measure of a cryptocurrency miner’s performance and a key security metric. In the context of mining, the more hashing or computing power in a given network, the greater its security and its overall resistance to attackMining hashrate is a key security metric. The more hashing (computing) power in the network, the greater its security and its overall resistance to attack. Hash rate is also a measurement of the output of a device that is used to add transactions to a blockchain ledgers that run on Proof-of-Work (PoW) algorithms.Hash Rate and Crypto MiningPoW algorithms require the computers that uphold the network and process transactions (called nodes) to solve complex equations in order to reach consensus, or agreement on whether or not a transaction. This process is called mining. Miners are chosen based on which one of them has the most powerful equipment--in other words, the highest hash rate. A hash rate is the measure of a cryptocurrency miner’s performance and a key security metric. In the context of mining, the more hashing or computing power in a given network, the greater its security and its overall resistance to attackMining hashrate is a key security metric. The more hashing (computing) power in the network, the greater its security and its overall resistance to attack. Hash rate is also a measurement of the output of a device that is used to add transactions to a blockchain ledgers that run on Proof-of-Work (PoW) algorithms.Hash Rate and Crypto MiningPoW algorithms require the computers that uphold the network and process transactions (called nodes) to solve complex equations in order to reach consensus, or agreement on whether or not a transaction. This process is called mining. Miners are chosen based on which one of them has the most powerful equipment--in other words, the highest hash rate. Read this Term. This can result in rewriting the chain history or even double-spending.

The recent attack on the network was revealed by mining pool operator, Bitfly, and crypto exchange, Binance, the first has halted all Ethereum Classic payouts for mining, while the exchange has suspended ETC withdrawals and deposits.

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

The developers of the cryptocurrency also urged the community to raise the confirmation time of any transaction involving Ethereum Classic following the attack.

In light of recent network attacks, it's recommended that all exchanges, mining pools, and other ETC service providers significantly raise confirmation times on all deposits and incoming transactions. @okex @binance @HuobiGlobal @hitbtc @coinbase @digifinex @etherchain_org

— Ethereum Classic (@eth_classic) August 6, 2020

The reorganized blocks have become the longest chain on the network, and the miners are now mining the other shorter version. Hash rate on the Ethereum Classic network has also dropped by around 20 percent since the beginning of the week.

A Vulnerable Blockchain Blockchain Blockchain comprises a digital network of blocks with a comprehensive ledger of transactions made in a cryptocurrency such as Bitcoin or other altcoins.One of the signature features of blockchain is that it is maintained across more than one computer. The ledger can be public or private (permissioned.) In this sense, blockchain is immune to the manipulation of data making it not only open but verifiable. Because a blockchain is stored across a network of computers, it is very difficult to tamper with. The Evolution of BlockchainBlockchain was originally invented by an individual or group of people under the name of Satoshi Nakamoto in 2008. The purpose of blockchain was originally to serve as the public transaction ledger of Bitcoin, the world’s first cryptocurrency.In particular, bundles of transaction data, called “blocks”, are added to the ledger in a chronological fashion, forming a “chain.” These blocks include things like date, time, dollar amount, and (in some cases) the public addresses of the sender and the receiver.The computers responsible for upholding a blockchain network are called “nodes.” These nodes carry out the duties necessary to confirm the transactions and add them to the ledger. In exchange for their work, the nodes receive rewards in the form of crypto tokens.By storing data via a peer-to-peer network (P2P), blockchain controls for a wide range of risks that are traditionally inherent with data being held centrally.Of note, P2P blockchain networks lack centralized points of vulnerability. Consequently, hackers cannot exploit these networks via normalized means nor does the network possess a central failure point.In order to hack or alter a blockchain’s ledger, more than half of the nodes must be compromised. Looking ahead, blockchain technology is an area of extensive research across multiple industries, including financial services and payments, among others. Blockchain comprises a digital network of blocks with a comprehensive ledger of transactions made in a cryptocurrency such as Bitcoin or other altcoins.One of the signature features of blockchain is that it is maintained across more than one computer. The ledger can be public or private (permissioned.) In this sense, blockchain is immune to the manipulation of data making it not only open but verifiable. Because a blockchain is stored across a network of computers, it is very difficult to tamper with. The Evolution of BlockchainBlockchain was originally invented by an individual or group of people under the name of Satoshi Nakamoto in 2008. The purpose of blockchain was originally to serve as the public transaction ledger of Bitcoin, the world’s first cryptocurrency.In particular, bundles of transaction data, called “blocks”, are added to the ledger in a chronological fashion, forming a “chain.” These blocks include things like date, time, dollar amount, and (in some cases) the public addresses of the sender and the receiver.The computers responsible for upholding a blockchain network are called “nodes.” These nodes carry out the duties necessary to confirm the transactions and add them to the ledger. In exchange for their work, the nodes receive rewards in the form of crypto tokens.By storing data via a peer-to-peer network (P2P), blockchain controls for a wide range of risks that are traditionally inherent with data being held centrally.Of note, P2P blockchain networks lack centralized points of vulnerability. Consequently, hackers cannot exploit these networks via normalized means nor does the network possess a central failure point.In order to hack or alter a blockchain’s ledger, more than half of the nodes must be compromised. Looking ahead, blockchain technology is an area of extensive research across multiple industries, including financial services and payments, among others. Read this Term

Notably, the fresh attack followed similar attacks on the Etheruem Classic blockchain between July 29 and August 1.

An analysis published on Wednesday by blockchain intelligence firm Bitquery detailed that the attacker paid around 17.5 BTC to gain 51 percent hash rate of the blockchain and double-spent over 800,000 ETC, valued around $5.6 million.

The details of this morning’s attack, however, is not yet known, meaning it is unclear how much the attacker spent and how many cryptos were double-spent. However, the attacker might have received $93,760 from blockchain mining rewards alone, given the $23.44 per block reward for Ethereum Classic mining.

Despite the attacks, the market value of the cryptocurrency did not take a hit as it is being traded sideways without any significant swing.