-: In this small section,
we are going to cover how we can use Nmap in our advantage
to be able to bypass some of the security measures
that the target might have, such as firewalls and IDS.
These options that we will use in Nmap
can be considered advanced,
so don't worry if you don't fully understand everything
that we talked about in the next few videos.
Just make sure that in case there is something that you
didn't understand, re-watch the video a few times
and you will get it.
But wait Alexa, I don't even know what firewall or IDS is.
So what are they?
Well, firewall is a network security system
that monitors network traffic, and it is based on
the security rules that are predetermined.
There are two types of firewalls:
Network firewalls and host-based firewalls.
Network firewalls filter traffic
between two or more networks,
while host-based firewalls only filter traffic
that is going in or out from that specific machine.
And what IDS is, is intrusion detection system.
It is usually a software application
that monitors network for any malicious activity.
For example, some of the Nmap scans
that we did in the previous section
can get caught by intrusion detection system.
So in this section,
we will check out a few options
that could help us bypass that.
All in all, firewall and IDS helps us
secure our network or machine.
In the previous section,
where we covered Nmap basics,
we used our Kali Linux machine
and we scanned our metasploitable target.
We scanned different ports,
and with the scans that we did,
we managed to figure out what ports are open
and what ports are closed.
But some of our targets might host services
on ports hiding behind the firewall,
and once we scan them
it will tell us those ports are filtered,
which we know that it means Nmap can't figure out
whether that port is open or closed.
What this means is that we're sending packets to the target,
but their firewall keeps dropping those packets.
And in this section,
we're going to see what Nmap options can help us
in bypassing this.
Let's get straight into it.