Port 1433 (Microsoft SQL Server)
Default port for SQL Server.
- Transport
- TCP
- Internet exposure
- Never expose
Should not be reachable from the internet.
Security notes
- Internet-exposed SQL Server faces constant brute forcing of the sa account.
- xp_cmdshell turns database access into operating system command execution.
When it shows up in your logs
Inbound 1433 from the internet is scanning or brute forcing.