Netcat, widely known as a net admin’s Swiss Army Knife, is a command line network utility that can read and write data across TCP and UDP network connections. It can be used as a powerful port scanner, port listener, port re-director and a backdoor to anyone who gets familiar with the commands.
All the tables provided in the cheat sheets are also presented in tables below which are easy to copy and paste.
The Netcat cheat sheet covers:
- Installation
- Run Modes
- Netcat Command Flags
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View or Download the cheat sheet PDF file
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What’s included in the cheat sheet
The following categories and items have been included in the cheat sheet:
Installation / Run Modes
Installation / Run Modes |
|
|---|---|
Client Mode | Connect to a host located anywhere |
Client Mode Syntax | nc options hostname port[1] port[2]... |
Server Mode | Listen for incoming connections |
Server Mode Syntax | nc -l -p port [hostname] [port] |
Netcat Command Flags
Netcat Command Flags |
||
|---|---|---|
Option | Description | Example |
-h | Help | nc -h |
-z (host name)(port range) | Port scan for a host or IP address | nc -z 10.1.1.1 1-100 |
-v | Verbose scan | nc -z -v 10.1.1.1 1-100 |
-n | Fast scan by disabling DNS resolution | nc -z -n 10.1.1.1 1-100 |
-l | TCP server mode | nc -l -p 50 |
> | Server file redirection | netcat -l -p 1000 > scan.txt |
< | Client file redirection | nc 10.1.1.1 1000 < scan.txt |
-k | Listen to port & IP address after connection close | nc -k -l 1000 |
-w | Define timeout value | nc -w 180 10.1.1.1 2222 |
-4 | IPv4 only | nc -4 -l 1000 |
-6 | IPv6 only | nc -6 -l 1000 |
Netcat FAQs
What is Netcat used for?
Netcat is a port scanner and monitor that can also be used to transfer files and execute transferred programs. It is of use to network administrators and it is also used by hackers.
Which option of the Netcat command allows it to scan multiple ports?
You can scan a range of ports with the Netcat command:
nc -zv hostname.com <port_from>-<port_to>
alternatively
nc -zv hostname.com <port_from> <port to>
How do I use Netcat on Windows?
Netcat is available in Windows but it doesn’t have an app with a graphical user interface. Instead, you have to enter cmd in the Start menu search field and click on Command Prompt in the results list. Enter an nc command at the prompt to run the service.
How do I scan a port using Netcat?
Netcat is a command-line utility that is launched with the letters nc followed by switches and a port number or range.
