https://www.bleepingcomputer.com/news/security/chinese-hackers-use-new-malware-to-backdoor-microsoft-sql-servers/

New malware created by Chinese-backed Winnti Group has been discovered by researchers at ESET while being used to gain persistence on Microsoft SQL Server (MSSQL) systems.

The new malicious tool dubbed skip-2.0 can be used by the attackers to backdoor MSSQL Server 11 and 12 servers, enabling them to connect to any account on the server using a so-called "magic password" and hide their activity from the security logs.