BlockBeats News, September 14, according to @OrangeFren, Monero suffered another attack. A few hours ago, XMR experienced an 18-block reorganization. When accepting XMR payments, be sure to wait for more than the usual 10 confirmations.
SlowMist Cosmos stated, "If no one in the Monero community takes the block reorganization issue seriously, the network will be hanging under the 'Sword of Damocles' for a long time. Even if the hashrate does not exceed 51%, there may still be a double-spend risk."