Skip to content

mdulin2/nmap_writeup

Folders and files

NameName
Last commit message
Last commit date

Latest commit

 

History

5 Commits
 
 

Repository files navigation

Nmap

Introduction

Nmap is a free network scanner, that has an amazing variety that people can use.
Just to begin, it can scan for open ports, versions of the server, scan whole subnets, check particular ports things... Nmap is an extremely versitle tool.
For the server that I set up, people need to notify to put it back up. For the specs on here, I will use IPADDRESS to symbolize it.

Installation

I would run this is a Linux virtual machine, in the terminal. So, that's how I'm going to explain it here.
Simply run:

sudo apt-get install nmap

and this should install it on ubuntu or Debian it should work. Kali Linux should already have a preinstalled set up of it on there. Other OS's installing nmap are defintely possible; just google or ask me if you have issues.

Terminal

To run nmap type this into the terminal:

nmap

This will open up the help screen for running nmap.

Knowledge

Ports

There are a few base things that need to be known before this will be understandable. On a network, there are 'ports'. These ports are used for connecting to the server. Even though they are more symbolic that anything now, this is what is used. Differeent ports have different responsiblilities. For instance, port 22 is used as the SSH port. SSH is how to remotely connect to a server. Another exampe is port 80 and 8008 are used for http connections.

Port Status

There are a few different types of statuses for a port. This statuses are practically representing the responding status of the port . Click here to learn more about these. In general, you'll only see open, closed and filtered. https://nmap.org/book/man-port-scanning-basics.html

Basic Commands

The basis of nmap is scanning an IP address. For this project, we're going to start with ada.gonzaga.edu. This is what im going to use for the rest of the examples, if not later specified.
To scan ada run

nmap ada.gonzaga.edu

This will give you open ports on the server, but that's about it.
To scan a singluar port run

nmap ada.gonzaga.edu -p port#

For multiple ports run

nmap ada.gonzaga.edu -p port#1,port#2

Now, scan the site 51.84.185.35....
Nothing comes up, right? Well, server have the ability to disallow ping responses. So, if this becomes an issue you can run:

nmap -Pn ada.gonzaga.edu

This will essentially run a test that is guarenteed to find the result of each port.
Scanning for a version service

nmap -sV ada.gonzaga.edu

This commands takes a while so please be patient.
To do extremely verbose protocols, use the -A flag like

nmap ada.gonzaga.edu -p 80 -A

This will give the user practically as much information as they could ever need about the web server.

Importance

This is an extremely important tool to understand, for hacking and just networking in general. Finding open ports can lead to easy access on a server. Further, all of these open ports could potentially be connected, stealing information from it. The namp tool tends to access information that a regular user wouldn't see, such as the robots.txt file.
The flags up above are just the tip of the iceberg! Further, you can scan a whole subnet of domains and get way more spefific with what is going on in the scans, with different types of packets being sent and more.

Testing it

See what you can find on the site I set up at TBD.
Run all different types of scans and see what you can find. In particular, look for files that the owner would not want you to see.

SSH

SSH stands for secure shell. SSH allows you to connect to a web server without physcially being on the machine. In order to do this, the command for ada is

ssh student@ada.gonzaga.edu

However, there are more advanced features than this... A person can have a key set up for the server, instead of having a password into it. The syntax for that is

ssh -i key_file.pem student@ada.gonzaga.edu

This will allow you to log into a server with a key. Note, AWS keys use a ubuntu@.... for ec2 instances.

Learning basic networking

Here's how I learned what I know about it: Microsoft certification area: https://www.youtube.com/watch?v=t9TmvFvYfWw&list=PLAVVUE5_qTL0sujvs5pGySHl1pXuw1job Then, just googling things I did not know.

Website fun

So, using the mechanisms above it is possible to break into the server that I have set up. The IP address changes everytime that I turn it on. So, if you want to attempt to break into it, shoot me an email or text; then I'll set it up and let you know the IP address.
Using all of the tools above, a person can see a clear vulnerbility in the system. Run nmap IPADDRESS# -A.

Results

Nmap is extremely good at picking up on things when they are public. In this case, it was able to discover that all of the files on my website (IPADDRESS/GonzagaDodgeball/Information.html), that I was using a github repository, that a apache server is being used... And much much more. Do any of these files seem interesting to you that it shows? The one that show really catch a person's eye is the robots.txt file. To read more click http://www.robotstxt.org/
The robots.txt file is meant to prevent web scraping on certain parts of the website. But, the files not to be scraped are probably files that they don't want people to see. So, check this file out!
A file should be referenced in there; open that file now.

Logging in

I don't want to spoil the whole surprise. So, I don't tell you what the file is exactly.
Just a reminder though, for an AWS instance login for an EC2 instance, use ssh -i key.pem ubuntu@IPADDRESS

I'll tell you

Okay, the file above is a pem file, or a private key file used to access the server. Use it to login to the server that I set up! Remember, copy the whole file . Otherwise, it won't work for a login. Once you've downloaded the key, make sure to change the permissions of it, otherwise you'll have a ton of errors thrown at you! Use chmod +x key.pem to do this. The +x is for changing it to an executable, taking away write and reading privledges. This may seem really stupid but it actually happens quite frequently! Tesla recently had a server compromised for this same exact reason. https://www.wired.com/story/cryptojacking-tesla-amazon-cloud/

The End

Thanks for checking this out! I really enjoy my hacking and computer security jazz! If anyone has any idea or exploits, or just fun hacking projects please let me know. I would love to learn/help out on it! If anyone has any questions, feel free to call, email or text me about this.

About

No description, website, or topics provided.

Resources

Stars

Watchers

Forks

Releases

No releases published

Packages

 
 
 

Contributors