BTCPay Server reported that hot wallets on multiple instances are being drained by unauthorized attackers. The project urged users running BTCPay Server to immediately shut down their servers using the command `run./btcpay-down.sh` until the investigation is complete. The cause of the attack and the total scale of losses have not yet been disclosed. This incident follows an emergency update released on October 29, version 2.4.7, which patched one critical and several medium-risk security vulnerabilities in BTCPay Server.