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312-50V10 · Question #333

What results will the following command yield: 'NMAP -sS -O -p 123-153 192.168.100.3'?

The correct answer is D. A stealth scan, determine operating system, and scanning ports 123 to 153. The command combines three distinct Nmap flags: SYN stealth scan, OS fingerprinting, and a specific port range, making D the only fully accurate description.

Scanning Networks

Question

What results will the following command yield: 'NMAP -sS -O -p 123-153 192.168.100.3'?

Options

  • AA stealth scan, opening port 123 and 153
  • BA stealth scan, checking open ports 123 to 153
  • CA stealth scan, checking all open ports excluding ports 123 to 153
  • DA stealth scan, determine operating system, and scanning ports 123 to 153

How the community answered

(30 responses)
  • A
    3% (1)
  • C
    7% (2)
  • D
    90% (27)

Why each option

The command combines three distinct Nmap flags: SYN stealth scan, OS fingerprinting, and a specific port range, making D the only fully accurate description.

AA stealth scan, opening port 123 and 153

This misinterprets `-p 123-153` as opening only two discrete ports (123 and 153) rather than a range, and omits the OS detection behavior of `-O`.

BA stealth scan, checking open ports 123 to 153

While it correctly identifies the stealth scan and port range, it completely omits the OS detection function provided by the `-O` flag.

CA stealth scan, checking all open ports excluding ports 123 to 153

The `-p 123-153` syntax specifies ports to include in the scan, not exclude; exclusion requires the `--exclude-ports` option.

DA stealth scan, determine operating system, and scanning ports 123 to 153Correct

The `-sS` flag performs a TCP SYN (stealth) scan that never completes the three-way handshake. The `-O` flag activates OS detection via TCP/IP stack fingerprinting. The `-p 123-153` flag restricts scanning to that inclusive port range, so all three behaviors occur simultaneously.

Concept tested: Nmap SYN scan with OS detection and port range

Source: https://nmap.org/book/man-briefoptions.html

Topics

#Nmap#stealth scan#OS detection#port scanning

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