TCP port 1433 is the well-known default port for Microsoft SQL Server, formally registered as ms-sql-s. In CEH network and perimeter security coverage, identifying services by their default port assignments is a critical reconnaissance and defensive skill. When reviewing firewall rules and exposed services, analysts correlate open ports with their associated protocols to determine risk exposure. Port 1433 is widely recognized as the primary listening port for Microsoft SQL Server instances configured with default settings.
The presence of an undocumented virtual machine actively handling traffic on port 1433 is particularly concerning because database services often store sensitive operational or customer data. If exposed unnecessarily, SQL Server can be targeted for brute-force authentication attacks, SQL injection exploitation, misconfiguration abuse, or exploitation of unpatched vulnerabilities. CEH materials emphasize that database services should not be directly exposed to the internet unless absolutely necessary and must be protected by strict access controls, segmentation, encryption, and monitoring.
Option B, SqlNet, typically refers to Oracle database communication over port 1521. Option D, ms-sql-m, is associated with SQL Server Browser service over UDP 1434, not TCP 1433. Option A, sqlsrv, is not the formal IANA-registered service name for port 1433. Because ms-sql-s is the standard designation for Microsoft SQL Server on TCP port 1433, and given the risk of exposing database services, this finding warrants immediate escalation and review.