One transfer between wallets was accounted for twice because of a miner conflict. As a result, the blockchain of the first cryptocurrency split into two chains
The bitcoin network experienced a minor disruption. The research department of derivatives platform BitMEX Research reported that yesterday, January 20, the cryptocurrency’s blockchain on block 666833 was found to be double-wasted – a single transaction to transfer 0.00062063 BTC was accounted for twice. At the current exchange rate, that’s about $21.
Researchers explained that there was a conflict between two SlushPool and F2Pool mining pools on block 666833. As a result, two block chains were formed. One of them recorded a transfer of 0.00062063 BTC to purse 1D6aebVY5DbS1v7rNTnX2xeYcfWM3os1va. In another, the transfer amount was also 0.00062063 BTC, but only 0.00014499 BTC reached the recipient, the rest was spent on commission.
“There seems to have been a small double spend… In one chain, 0.00062063 BTC was sent. In the other chain, the same amount of coins were spent, but only 0.00014499 BTC left,” the analysts wrote.
The conflict between the mining pools was won by SlushPool, as the chain of blocks it found was longer than the chain of a competitor, BitMEX clarified. Thus, only the transfer of 0.00014499 BTC is considered valid in the bitcoin network. A second transaction of 0.00062063 BTC is considered invalid.
This is confirmed by data from blockchain.com’s blockchain observer. The service displays information on the 0.00014499 BTC transaction correctly. If you check a transaction of 0.00062063 BTC, the observer shows the transaction as invalid.
Later BitMEX researchers wrote in their Twitter account that the cause of the incident could be a replace-by-fee (RBF) attack. It is a manipulation when an attacker tries to gain access to a cryptocurrency wallet by intercepting the sender’s transaction by paying a higher fee.
Double spending is when a random user or attacker manages to spend the same amount of money twice. For example, sending 1 BTC between wallets twice, resulting in two coins arriving at the end address. A similar thing happened in August on the EthereumClassic network. At that time, an unknown person made two “51% attacks” on the altcoin blockchain. During the first one he applied the principle of double spending and, having doubled the initial amount of ETCs, embezzled $5.6 million.
