On September 14th, according to @OrangeFren, Monero (XMR) has once again been attacked. A few hours ago, XMR experienced a reorganization of 18 blocks. When accepting XMR payments, it is necessary to wait for more than the usual 10 confirmations.
SlowMist Cosine expressed that if no one in the Monero community takes the block reorganization seriously, the network will be hanging under the "Sword of Damocles" for a long time, and there may still be a risk of double spending even if the computing power does not exceed 51%.