Explained: What Is A 51% Attack on Blockchain and Bitcoin?

The blockchain’s decentralized nature and the cryptographic algorithm is close to impossible for attacks. Yet, the Ethereum Classic falls victim to this malicious with an estimated loss of $1.1million for the 51% attack. So, what is a 51% attack, and how it happens?

A 51% attack (51 percent attack) is a type of blockchain infiltration that can cause network disruption and, eventually, mining monopolization. This attack occurs when a miner, an organization, or a single entity gains over 50% majority control of the hash rate or computing power runs on the blockchain’s network.

As a result of the attack, the attackers acquired access to prevent miners from mining, cancel transactions, and ultimately run off with stolen coins that have never belonged to them.

When the blockchain network is hijacked, the attacker would have sufficient mining power to modify a transaction. That means an ordering transaction can be modified, and all mining activities can be put at a halt. That’s precisely how a 51% attacker reverses a transaction that causes double-spending within the blockchain.