We’ve learnt now that no system created by human beings is invulnerable, overtime weaknesses will be found and exploited – an example of this is a 51% attack in crypto.
A 51% attack in cryptocurrency is when a malicious actor or group of actors control a majority of the computing power (hashrate) in a Proof-of-Work (PoW) blockchain network.
This gives attackers the ability to control the network and manipulate transactions, allowing them to double-spend coins, block transactions, and even reverse transactions. The attacker can also prevent new transactions from being confirmed and stop other miners from mining.
The attack can be done by either owning enough mining power, or by renting the power from other miners. The attacker can also use a combination of both strategies. This type of attack is one of the biggest threats to the security of a blockchain-based cryptocurrency.