On an episode of Good Morning Crypto, the recent 51% attack on Ethereum Classic (ETC) was discussed. Double spending took place on the ETC amounting to approximately $400,000 to $500,000. The longest chain wins in all proof-of-work blockchains, which is key to understanding how the double spending happened. The attacker created a secret block that showed a transaction from A to A, while the public block showed the same transaction from A to B. By mining the secret chain faster than the public chain, the attacker was able to replace the public chain with their own. Coinbase has blocked all ETC activity until the issue is resolved.
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Introduction
In this episode of Good Morning Crypto, we discuss the recent 51% attack on Ethereum Classic, which resulted in double spending and the reorganization of the chain. We’ll take a look at how this happened, the blogs that were affected, and the new mining risks associated with Ethereum Classic.
Live from Stockholm
We are live from Stockholm, Sweden, broadcasting each and every day at 8 a.m. Central European Summer Time. Today, we will focus on Ethereum Classic and the recent 51% attack that occurred.
Explaining the Attack
Ethereum Classic was hit with a 51% attack, which resulted in double spending of approximately four to five hundred thousand dollars. This happened when someone sent money and then reversed that transaction by reorganizing the chain and removing the already confirmed transactions from the blockchain.
We will explain exactly how this happened and discuss the blogs affected by the attack. Coinbase has blocked all Ethereum Classic activity until the issue is resolved. We will also look at the new mining rigs that are believed to be the cause of the attack, which specialize in mining Earthash and Shash, the mining algorithms of Ethereum Classic and Ethereum.
The Golden Rule of Blockchain
To fully comprehend the attack, it is important to understand the mechanics of blockchain technology, specifically the “golden rule.” This rule states that the longest chain wins, meaning that if a chain is produced that is longer than the current public one, that chain will replace the previous one as the valid chain.
Double Spending on a Proof-of-Work Blockchain
Transactions are bundled in blocks that contain multiple transactions, and a double spend attack occurs when someone creates a block with a transaction from A to B and secretly creates another block with the same transaction but from A to A. Both blocks have the same parent, but the private one is mined faster so that in the future, it can replace the current public chain, with the attacker in control of the valid chain.
More Hash Power is Key
To achieve this, the attacker needs more than 51% of the total hash power of the network. This means that they need to mine faster than everyone else and keep the private chain secret until it is long enough to replace the real chain.
Conclusion
The recent attack on Ethereum Classic has highlighted the importance of securing the network against 51% attacks. It is clear that the attacker took advantage of the lack of hash power on the network to successfully reorganize the chain and carry out double spending. The incident serves as a reminder that the network must remain vigilant in protecting against such attacks.
We hope you have learned from this episode of Good Morning Crypto. Don’t forget to sign up for Ivan on Tech’s Academy and stay tuned for our upcoming gaming course on blockchain technologies. Join the conversation in the chat, smash the like button, and tell us what you learned in the comment section below.
