Nessus- my experience using it for the first time.
I admit I am rather new to the cyber security sphere. As part of my desire to enter the field as a SOC analyst in my spare time I wanted to familiarise myself with the vital tools at their disposal. Nessus seemed like a good place to start. I had spoken to people who were already in cyber blue teams/SOC roles they had told me how crucial this vulnerability scanner is in terms of detecting open ports and potential attack vectors on a network. On a windy, wet and rainy Wednesday afternoon I decided to begin my foray into the murky world of Nessus…
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I started out with scanning my PC’s IP address to see if there were many vulnerabilities, I was half-expecting several a flash of red critical vulnerabilities to be returned. This was not to be, as we shall see. I initially had to find out what my IP address was (simply obtained by going into Window’s settings) and then running a basic scan on Nessus. The below picture revealed several information warnings but nothing of immediate concern (much to my relief!).
The basic network scan (because I am a poor recent graduate and am not paying for the professional version) brought back 98 informational vulnerabilities and 4 medium vulnerabilities. Upon examining these vulnerabilities most of the 98 informational were regarding open private ports. Of more interest to me was the 4 medium vulnerabilities. They in fact were regarding a SSH self-signed certificate. I immediately knew what this was, essentially when I had downloaded Nessus and gone to the webpage to access the interface I was doing this on a self-signed certificate- much to the chagrin of Microsoft defender.
I then wanted to test my Nessus scanner on a VM. After a while setting up an Ubuntu VM on Virtual box I was good to go. I made to sure to optimise the network settings to allow for a complete network scan. I opened up port 22 and disabled the firewall. Rather oddly, it kept on returning only one info vulnerability. I even made sure I was getting the IP address right by using the ping command from my host PC and packets were being returned. I can only assume that either scan of VM was failing due to some misconfiguration on either the VM’s network OR that given it was an empty Ubuntu VM there was very little going on. Either way for my first attempt I was happy that I had been able to set up Nessus, create a functioning VM, perform Linux commands on this VM and identify different types of vulnerabilities returned by Nessus. Not bad for a first go. Next goal is to deploy and use a SIEM tool.
