Linux ethical hacking

1. Hacker’s OS – Mastering Linux for Security
 Day 3: Linux Essentials & Hacking Lab Setup
 Become comfortable using Linux as your primary hacking
platform.

2. What is
Linux?
 Linux is a free, open-source operating
system used widely in cybersecurity.
 Distros: Kali, Ubuntu, Parrot OS.
 Key Traits: Lightweight,
customizable, terminal-based power.

3. Linux vs Windows for Hackers
Linux: Open-source, better control,
scripting, tools like Nmap,
Wireshark preinstalled.
Windows: GUI-heavy, less
flexibility for deep system control.

4. Why Do Hackers Prefer Linux?
 • Strong community and documentation
 • Security-centric distros like Kali
 • Control over networking and permissions
 • Scripting and automation potential

5. Kali Linux Overview
Kali is a Debian-
based Linux distro
built for penetration
testing.
Includes pre-
installed tools:
Nmap, Metasploit,
Wireshark, Burp
Suite.
Used by ethical
hackers globally.

6. File System Hierarchy
/ (ROOT) /BIN – ESSENTIAL
BINARIES
/ETC – CONFIG
FILES
/HOME – USER
FOLDERS
/VAR – LOGS AND
VARIABLE DATA
UNDERSTANDING
STRUCTURE IS KEY
FOR FILE ACCESS.

7. Navigating the File System
 `cd`, `ls`, `pwd`, `tree`
 Example:
 cd /home/user
 ls -l
 pwd shows current directory
→

8. File Management Commands
 `cp` – copy
 `mv` – move/rename
 `rm` – delete
 `touch` – create file
 `nano` – edit file

9. Viewing File
Content
 `cat` – view file
 `less` – scrollable view
 `head`/`tail` – show beginning/end
 Use for analyzing logs or script
output.

10. Searching Files
 `grep` – search within files
 `find` – locate by path/name/type
 `locate` – quick filename search via database

11. File Permissions Explained
 r = read, w = write, x = execute
 Example: rwxr-xr--
 Owner/User/Other
 Use `ls -l` to view permissions.

12. Changing
Permissions
 `chmod` – change file mode
 `chown` – change file
ownership
 Example:
 chmod +x script.sh
 chown user:user file.txt

13. User and Group Management
`adduser`,
`deluser`,
`passwd`, `su`,
`sudo`
Use `sudo` for
root privileges.
Groups control
access rights.

14. Understanding Root Access
Root = highest
privilege user
1
Use cautiously.
2
Always prefer
`sudo` over
direct root
login for safety.
3

15. Virtualization – Why VMs?
• Safe hacking
practice
• Easy to reset
system state
• Tools: VMware,
VirtualBox
• Isolated
environment for
attacks

16. Creating
Your
Hacking
Lab
1
🔹 Install
VMware or
VirtualBox
2
🔹
Download
Kali Linux
ISO
3
🔹 Set RAM
(2-4 GB) &
disk space
(20+ GB)
4
🔹
Configure
network
(NAT or
Bridged)
5
🔹 Optional:
Add target
machines
like
Metasploita
ble

17. Installing Kali Linux
Steps: 1. Download
ISO
2. Create VM 3. Allocate
RAM & Storage
4. Boot and
Install
5. Configure
User & Update

18. System Updates
 `sudo apt update`
 `sudo apt upgrade`
 Ensure latest packages and
security patches are installed.

19. Network Setup in VMs
MODES: • BRIDGED – VM
ACTS LIKE REAL
DEVICE
• NAT – SHARES
HOST IP
• HOST-ONLY –
ISOLATED FROM
INTERNET

20. Installing Tools – Nmap
`sudo apt install nmap` Used for port scanning
and network discovery.

21. Installing Tools – Wireshark
 `sudo apt install wireshark`
 Captures and analyzes network traffic.
 Must run with elevated privileges.

22. More Tools to Install
`SUDO APT INSTALL
NET-TOOLS NIKTO
HYDRA`
NET-TOOLS:
NETWORKING
COMMANDS
NIKTO: WEB
SERVER SCANNER
HYDRA: BRUTE-
FORCE LOGIN TOOL

23. Keeping Tools Updated
`sudo apt update && sudo apt upgrade`
Set regular update schedule
Prevents tool failure due to outdated
dependencies.

24. Introduction to Bash Scripting
Used to automate tasks
Written in `.sh` files
Execute with: `bash script.sh` or
`./script.sh`

25. Writing a Simple Script
Example:
#!/bin/
bash
apt update
&& apt
upgrade -y
Script runs
system
update

26. Command Chaining
`&&` – run second
command only if first
succeeds
`||` – run second if
first fails
`;` – run all regardless
of result

27. Looping and Conditions
Use `for`,
`while`, and
`if` statements
1
Automate
scans or
backups
2
Example: `for
ip in ...; do
nmap $ip;
done`
3

28. Making Scripts Executable
`chmod +x
script.sh`
Allows script
to be run
with
`./script.sh`

29. Practice Task: System Update Script
CREATE A
SCRIPT TO:
• UPDATE
SYSTEM
• PRINT
DATE/TIME OF
UPDATE
• LOG RESULTS
TO A FILE

30. Summary & Learning Outcome
You now:
• Understand Linux structure
• Can navigate, modify files
• Set up Kali Linux
• Install and use hacking tools
• Write and execute Bash scripts

31. What’s Next?
 Prepare for Day 4: Reconnaissance & Scanning
 Install tools: WHOIS, nslookup, Nmap
 Review Bash scripting
 Practice using commands learned today