The misleading news double-spend attack first became news and a trending topic on Twitter after BitMex Research reported on block 666,833’s misleading information on Twitter. The reorganization meant a “stale block” (also sometimes called an “orphan block”) had been mined that contained bitcoin also spent on Bitcoin’s valid blockchain, so a transaction containing the same bitcoin was recorded on both the relevant and irrelevant chains.
What BitMEX research called at first a “double-spend-like scenario” now looks like a brilliant storm caused by the one block reorg and a replace-by-fee transaction. A RBF transaction occurs when you tell your wallet to send the same bitcoin again but with a higher fee, with the hopes that it will be confirmed before the lower fee transaction.
What really happened was a impatient buyer who tried to outpace the system: Someone sent 0.00062063 BTC to this address but set the cheapest fee possible (1 satoshi per byte, or less than a fraction of a cent, per byte of transaction data).
Since the fee was so cheap, the transaction took a longer than usual to confirm, so the buyer couldn’t wait so they decided to rush and send a RBF what’s called a “replace by fee transaction” (RBF).
Instead of the RBF replacing the slow transaction as intended, however, the lower fee transaction cleared first and made it into the block that was mined onto the longest chain.
Meanwhile, the higher fee transaction found its way onto the stale block. The final result: 0.00062063 BTC is recorded as existing on the address 1D6aebVY5DbS1v7rNTnX2xeYcfWM3os1va on the irrelevant transaction history while 0.00014499 BTC exists on the same address but on the relevant tran