Cyber Security… Port scanning with NMAP!

Andrea Pollastri
1 min readFeb 20, 2024

If we are to defend, we first need to know what to defend. Asset Management often relies on Network Mapping to identify which systems are live on a network.

Asset management and knowing what you expose on the network, including which services are hosted is very important for anyone looking to defend their network.

Nmap is a network scanner created by Gordon Lyon (also known by his pseudonym Fyodor Vaskovich) and it’s used to discover hosts and services on a computer network by sending packets and analyzing the responses.

The first step to use is, is install it!

If you have a Mac, use Brew:

brew install nmap

Now you are ready to run a check:

 nmap TARGET

Where TARGET is a domain name ( or an IP (

The response is a list of open ports (potentially vulnerable) related to host services. This situation could help any hacker to attack your system.

You can also add verbosity using:

 nmap TARGET -sV

Or extend the range of ports to check (this will require several minutes):

 nmap TARGET -p- -sV

Find more info here: