Hang on, before rushing in to start our first Nessus scan, I'd like to show you how to create our
own policies.
Policies allow you to create custom templates defining what actions are performed during a scan in the
Nessus Web interface click policies at the left side.
You see that good click the create a new policy link inside the policies page.
Now here we have a lot of scanners, so an advance scan.
All the options are chosen by us without any guidance or recommendations.
Basic network scan is generally suitable for any host.
Internal PCI network scan is designed for internal scans and it's based on PCI disc standard.
PORKED Midsouth Payment Card Institute and data security standards simply one of the most important
information security standards.
So it looks like the days when this video was captured, that spectre and meltdown are the are really
new vulnerabilities.
So here there is a scan specialized where specter and meltdown vulnerabilities.
This clearly shows how up this is is here.
There's another scanner specific for Web applications.
So let's configure our own scan, click, advance scan first, give a name for your policy.
Now go to Discovery section, so we're in the host discovery page here, we have a ping, the remote
host option and the settings of the ping.
If we're going to use the data we collected, then map, we can close this ping scan because we already
have the lists of the hosts click port scanning to configure port scanning options.
The default value of the ports gain ranges will default.
That means Nessus will scan the ports, which is in its Nessa's services file.
Now I go to the terminal screen to analyze Inessa services file.
Let's find the file first.
Use the fine command to find the file means that the search will begin from the root directories.
Dasch name shows the name of the search file and hit Enter, and here it is, you can stop the search
using control keys.
I use the less command to see the content of the file.
Here are the ports protocols and the default services which use these ports.
Now I want to see the number of the lines of Nessa's services fail to understand how many ports are
scanned by default.
Cat command with a file name pipe that you see to see the word count.
The first number is the number of lines, a second one is a number of the words, and the last one is
the number of the characters.
So we can say that 9000 ports are scanned by default, which is a total of both TCP and UDP ports,
but what have you want to see the number of TCP ports scanned by default, you can use grep before we
see type cat filename PYT grep TCP pipe.
See, you will see the number of TCP ports scanned by default.
There are about 4600 exports now, if you want to scan for all ports, you should type one through six,
five, five, three, five and ports can range for you.
So here are the options to use S8 service for a local board, a numerators, so let's have a short break
here.
If you have some credentials to scan some services in depth, you can define those credentials before
the scan.
So here, select your credentials tab and you see some services when you click the S.H., for example.
You will see the credential options, but let's remove this for now.
Now turn back to settings by clicking its tab.
We were in Discovery Port scanning page and here the port scanning options.
Since scan is selected by default, if you like, you can select TCP and or UDP scans as well.
Now go to the advanced section.
Safe checks are enabled by default.
So we can select scan IP addresses in a random order to make the scan a little more stealthy.
Let's look at the performance options.
We can reduce the number of Macs simultaneous hosts per scan to avoid delays and network traffic.
Max, number of concurrent TCP sessions per host is not defined by default, we can define an upper
bound to keep the hosts safe.
And again, we may define a maximum number of concurrent TCP sessions per scan to keep the network traffic
safe.
Now look at the tabs on the top of the new policy page and you'll see the plug ins tab.
Right.
So here we have tons of plug ins used in Nessa's scans.
If you click one of the plug in families, you'll see all the plug ins of that family.
You see the total number of plug ins and a plug in family.
And here the plug ins.
You can click on Enabled next to a plug in to disable it.
Or if you want to disable an entire plug in family entirely, for example, denial of service, click
on Enable labeled next to the name of the plug in family click save.
And now we have our own Skåne policy.