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GPEN · Question #265

Which of the following nmap switches is used to perform ICMP netmask scanning?

The correct answer is A. -PM. The nmap -PM switch sends ICMP address mask requests (type 17) to probe live hosts, distinct from other ping types.

Vulnerability Discovery & Scanning

Question

Which of the following nmap switches is used to perform ICMP netmask scanning?

Options

  • A-PM
  • B-PB
  • C-PI
  • D-PS

How the community answered

(35 responses)
  • A
    74% (26)
  • B
    6% (2)
  • C
    17% (6)
  • D
    3% (1)

Why each option

The nmap -PM switch sends ICMP address mask requests (type 17) to probe live hosts, distinct from other ping types.

A-PMCorrect

The -PM flag in nmap triggers an ICMP netmask (address mask) scan by sending ICMP type 17 address mask request packets. This is used for host discovery when standard echo requests are blocked, as some firewalls allow mask requests through. It is a specific host discovery technique separate from echo-based ICMP scanning.

B-PB

-PB performs a combined TCP and ICMP ping scan, not an ICMP netmask scan.

C-PI

-PI sends ICMP echo (ping) requests for host discovery, which is a standard ICMP echo scan, not a netmask scan.

D-PS

-PS performs a TCP SYN ping scan targeting specified ports, and does not use ICMP at all.

Concept tested: nmap ICMP address mask host discovery switch

Source: https://nmap.org/book/man-host-discovery.html

Topics

#nmap#ICMP scanning#netmask scan#host discovery

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