Which Port Scan Range value instructs the scanner to scan only common ports?

Which Port Scan Range value instructs the scanner to scan only common ports?

• A. 1-65535
• B. 1-1024
• C. default
• D. common

Answer: (C)

The correct choice indicates that using a default range for a port scan will typically target only the common ports. Common ports are those that are frequently used by many services and applications, making them important to check for vulnerabilities. Scanning the default range usually includes ports such as HTTP (port 80), HTTPS (port 443), FTP (port 21), and several others that are most likely to be exploited by attackers. This approach allows a more focused and efficient assessment by concentrating resources on the most critical and commonly used services, thus potentially revealing security issues without the overhead of scanning all possible ports. In contrast, scanning all ports from 1 to 65535 would examine every single port available, which is often unnecessary for most assessments and can lead to longer scan times and larger amounts of data to analyze. A narrower range such as 1-1024 also targets fewer common ports, but it does not fully capture the flexibility that scanning using the default settings offers. The term "common" by itself lacks specificity in the context of port scanning parameters, making it less clear what range would be scanned. Using the default option provides a standard method that aligns with best practices for efficient vulnerability assessment.

The correct choice indicates that using a default range for a port scan will typically target only the common ports. Common ports are those that are frequently used by many services and applications, making them important to check for vulnerabilities.

Scanning the default range usually includes ports such as HTTP (port 80), HTTPS (port 443), FTP (port 21), and several others that are most likely to be exploited by attackers. This approach allows a more focused and efficient assessment by concentrating resources on the most critical and commonly used services, thus potentially revealing security issues without the overhead of scanning all possible ports.

In contrast, scanning all ports from 1 to 65535 would examine every single port available, which is often unnecessary for most assessments and can lead to longer scan times and larger amounts of data to analyze. A narrower range such as 1-1024 also targets fewer common ports, but it does not fully capture the flexibility that scanning using the default settings offers. The term "common" by itself lacks specificity in the context of port scanning parameters, making it less clear what range would be scanned. Using the default option provides a standard method that aligns with best practices for efficient vulnerability assessment.