Learn the fundamentals of cybersecurity, threat landscapes, and security principles.
Cybersecurity is the practice of protecting systems, networks, and programs from digital attacks. These cyberattacks are usually aimed at accessing, changing, or destroying sensitive information, extorting money from users, or interrupting normal business processes.
In this module, you'll learn the fundamental concepts of cybersecurity, understand common threats, and get hands-on experience with ParrotOS security tools.
Cybersecurity encompasses multiple layers of protection spread across computers, networks, programs, and data. In an organization, the people, processes, and technology must all complement one another to create an effective defense from cyber attacks.
Key Principles (CIA Triad):
Imagine a hospital's patient database being compromised. Attackers gain access to:
Impact:
Malicious software designed to damage or gain unauthorized access to systems.
Types:
Fraudulent attempts to obtain sensitive information by disguising as a trustworthy entity.
Example Email:
From: [email protected] (notice the "1" instead of "l")
Subject: Urgent: Verify Your Account
Your account has been compromised. Click here to verify:
http://fake-paypal-login.com
Intercepting communication between two parties without their knowledge.
Common Scenarios:
Overwhelming a system with traffic to make it unavailable.
ParrotOS is a Debian-based Linux distribution designed for security testing, digital forensics, and privacy protection. It comes pre-installed with hundreds of security tools.
# Check system information
uname -a
# View OS release information
cat /etc/os-release
# Check current user
whoami
# List all users
cat /etc/passwd
# Display network interfaces
ifconfig
# Show active network connections
netstat -tuln
# Check routing table
route -n
# Test connectivity
ping -c 4 google.com
# List files and directories
ls -la
# Change directory
cd /home/user/Documents
# Print working directory
pwd
# Create directory
mkdir security_tools
# Remove file
rm filename.txt
Information gathering is the first phase of any security assessment. Here's how to use ParrotOS tools:
Nmap (Network Mapper) is a powerful network discovery and security auditing tool.
# Basic host discovery
nmap 192.168.1.1
# Scan specific ports
nmap -p 80,443 192.168.1.1
# Service version detection
nmap -sV 192.168.1.1
# OS detection
sudo nmap -O 192.168.1.1
# Comprehensive scan
sudo nmap -A -T4 192.168.1.1
Real-World Example: A security consultant needs to audit a company's network:
# Discover live hosts
sudo nmap -sn 192.168.1.0/24
# Scan discovered hosts for open ports
sudo nmap -p- -T4 192.168.1.100
# Identify services and versions
sudo nmap -sV -sC 192.168.1.100
# DNS lookup
nslookup example.com
# Reverse DNS lookup
nslookup 8.8.8.8
# DNS zone transfer attempt
dig @ns1.example.com example.com axfr
Use Strong Passwords
Enable Two-Factor Authentication (2FA)
Keep Software Updated
# Update ParrotOS
sudo apt update && sudo apt upgrade -y
Be Cautious with Public WiFi
Regular Backups
# Create encrypted backup
tar -czf backup.tar.gz /home/user/important_files
gpg -c backup.tar.gz
Implement Defense in Depth
Security Awareness Training
Incident Response Plan
Access Control
# Gather information about target
whois example.com
nslookup example.com
dig example.com ANY
# Discover live hosts
sudo nmap -sn 192.168.1.0/24
# Port scanning
sudo nmap -p- -T4 192.168.1.100
# Service enumeration
sudo nmap -sV -sC -p 22,80,443 192.168.1.100
# Banner grabbing
nc 192.168.1.100 80
HEAD / HTTP/1.0
# Run vulnerability scan
sudo nmap --script vuln 192.168.1.100
Ethical hacking involves authorized attempts to gain unauthorized access to systems, applications, or data. Ethical hackers use the same techniques as malicious hackers but with permission.
Always Remember:
Key Laws:
Many companies offer bug bounty programs where ethical hackers can report vulnerabilities for rewards:
Security Analyst
Penetration Tester
Security Engineer
Forensic Analyst
Security Architect
✅ Cybersecurity protects systems, networks, and data from digital attacks
✅ The CIA Triad (Confidentiality, Integrity, Availability) forms the foundation of security
✅ Common threats include malware, phishing, MITM attacks, and DoS/DDoS
✅ ParrotOS provides a comprehensive toolkit for security testing
✅ Information gathering is the first step in security assessments
✅ Always obtain authorization before conducting security tests
✅ Continuous learning is essential in the ever-evolving cybersecurity landscape
System Exploration
uname -a and document the outputifconfigNetwork Discovery
nmap to scan your local networkSecurity Research
Tool Familiarization
Websites:
Practice Platforms:
Books:
Now that you understand the fundamentals of cybersecurity, you're ready to:
Remember: Cybersecurity is a journey, not a destination. Stay curious, keep learning, and always practice ethically!