BCH saw a 2-block reorg post hardfork, resulted over 3K BCH double spent

Bitcoin Cash network experienced a 2-block reorganization right after hardfork, BitMEX research considers it "not positive".

Bitcoin Cash (BCH) saw a 2-block reorganization, which caused some of the transactions from the orphaned blocks failed to make it into the main chain. Based on BitMEX research’s calculation, as many as 3,392 BCH may have been double spent successfully in what is claimed to be an orchestrated transaction reversal.

However, it’s not yet clear whether the reorganization was done deliberately or accidentally.

The incident happened after the network underwent a scheduled hardfork on May 15th. According to The Block Crypto, an attacker successfully exploited a bug, which could have been done prior to the hardfork, by sending transactions that fulfilled the requirements of a valid transaction but failed the consensus checks. It resulted in empty blocks produced by miners.

Such incident is considered as concerning, despite the increase of hash rate up to 22 times higher post the hardfork.

“In some ways, these incidents contribute to setting a dangerous precedent. It shows that it may be possible in Bitcoin. Alternatively, this could just illustrate the risks Bitcoin Cash faces while being the minority chain,” BitMEX report stated.