To be able to theoretically modify the records on the Bitcoin network, the attacker would have to control more than 50% of the processing power of the cryptocurrency - that is, the equipment used to keep the blockchain running. This type of attack is called “51% Attack”.

According to the study, however, it would be necessary to acquire at least 7 million ASICS - the name of the machines used in Bitcoin mining - to achieve such a type of control. But there is no such amount of available hardware on the market.

“These ASICs are not for sale, but if a state attacker had enough resources to manufacture ASICs, the cost of manufacturing would be above $20 billion,” Nuzzi wrote on X (formerly Twitter), referring to a specific model (the AntMiner S9). 
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