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Laiba Nasir
Laiba Nasir

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NETCAT-A Hacking Tool

Introduction:

NetCat is a featured networking utility which reads and writes data across network connections, using the TCP/IP protocol.
It is designed to be a reliable “back-end” tool that can be used directly or easily driven by other programs and scripts. At the same time, it is a feature-rich network debugging and exploration tool, since it can create almost any kind of connection you would need and has several interesting built-in capabilities.

Earlier Version:

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The original version of NetCat was a UNIX program.
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Latest Version:

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The last version (1.10) was released in March 1996. There are several implementations on POSIX systems, including rewrites from scratch like GNU NetCat or Open BSD NetCat, the latter of which supports IPv6 and TL.
In 2000, it also voted the second most functional network security tool

Why This Tool?

NetCat functions as a back-end tool that allows for port scanning and port listening. In addition, you can actually transfer files directly through NetCat or use it as a backdoor into other networked systems
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Applications:

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Hackers:
Most common use for NetCat when it comes to hacking is setting up reverse and bind shells, piping and redirecting network traffic, port listening, debugging programs and scripts and banner grabbing

Installation:

Step 1: search NetCat for windows in chrome And open the first link https://eternallybored.org/misc/netcat/
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Step 2: Download the zipped folder and extract it
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Step 3: Put the folder in C:Windows\folder as follow
Step 4: run nc64.exe
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Step 5:
Now open the folder and run nc.exe file
After run that file you can check that NetCat is installed by opening the cmd and type nc -h. If it runs properly than it is installed successfully.
Note:
Sometime we may get some issues when we copy the extracted folder and placed it in C:\window folder then we have to open the window security and then check virus threat protection then go to manage settings and turn off real time protection after this we can easily placed the folder in C:\window folder.
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Commands:

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First open command prompt and type



   nc –h


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This command will print a list of all of the available commands you can use in NetCat. It will come in handy if you run into any errors while writing a script or are unsure of how to proceed.
nc -z -v site.com:
This will run a basic port scan of the specified website or server. NetCat will return verbose results with lists of ports and statuses. Keep in mind that you can use an IP address in place of the site domain.



nc -l


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This command will instruct the local system to begin listening for TCP connections and UDP activity on a specific port number
nc site.com 1234 (less than) file_name
This command will initiate the transfer of a file based on the specified port number.



 Printf:


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NetCat can actually operate as a simplified web host. This command will let you save HTML code and publish it through your local server.
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Port Scanning with NetCat Commands

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When trying to diagnose a network issue or performance problem, executing a port scan with NetCat is a smart first step to take. The scan will check the status of all ports on the given domain or IP address so that you can determine whether a firewall or other blocking mechanism is in place.
A basic port scan command for an IP ncat address looks like this:



nc -v -n 8.8.8.8 1–1000


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If you don’t know the IP address of a server or website, then you can look it up via a
ping terminal command or just insert the domain into the NetCat command:



 nc -v -n google.com 1–1000


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You should always perform port scans when connected to your local enterprise network. If not, you can configure your router with a VPN service to create a secure tunnel into the network
For instance, if you want to define a server or a client in the network for data transmission, the following syntax applies:
Client mode (connect to somewhere):



 nc[option][target-ip][port]


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Server mode (listen for inbound):



nc –l –p port [options][hostname][port]


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Copying files:

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A frequently used feature of NetCat is copying files. Even large quantities of data can be sent and individual partitions or entire hard drives cloned. In our example, the testfile.txt file is copied from computer A (client) to computer B (server) via port 6790: These steps are required:

  1. Determine the IP address of computer B (destination PC)
  2. Create the test filetestfile.txt in the NetCat folder of computer A; in this example, the fest file is located in the client’s NetCat folder. The copied file then ends up in the NetCat folder on computer B (other file paths need to be adjusted accordingly).
  3. Enter the NetCat syntax in the command line Computer B (acts as the receiving server):


nc –l –p 6790 > myfile.txt


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Computer A (acts as the sending client):



nc [IP-Address of computer B] 6790 <myfile.txt


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The success of the transfer is not confirmed in the command prompt. You can see whether the transfer worked by checking in the destination folder.
Hope you like this amazing tool if yes clap below 👏

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