1.Security Basics
1.1 CIA Triad| Concept | Description |
| Confidentiality | Protecting data from unauthorized access (Encryption, Access Control) |
| Integrity | Ensuring data is unaltered (Hashes, Digital Signatures) |
| Availability | Ensuring uptime and accessibility (Backups, Redundancy) |
| Type | Description | Example |
| Administrative | Policies and training | Security policies, awareness training |
| Technical | Technology-based security | Firewalls, antivirus, encryption |
| Physical | Protects hardware & facilities | Locks, security cameras, fences |
2.Threats, Attacks, and Vulnerabilities
2.1 Common Cyber Attacks| Attack Type | Description |
| Phishing | Deceptive emails to steal credentials |
| Spear Phishing | Targeted phishing attack |
| Smishing | SMS-based phishing |
| Vishing | Phone-based phishing |
| MITM (Man-in-the-Middle) | Intercepting communication |
| DDoS (Distributed Denial of Service) | Overwhelming a system with traffic |
| SQL Injection | Injecting SQL commands to manipulate databases |
| XSS (Cross-Site Scripting) | Injecting malicious scripts into web pages |
| Zero-Day Attack | Exploiting an unknown vulnerability |
| Type | Description |
| Virus | Attaches to files and spreads |
| Worm | Self-replicating malware |
| Trojan | Disguised as legitimate software |
| Spyware | Secretly gathers information |
| Ransomware | Encrypts files for ransom |
| Rootkit | Hides system-level access |
3.Risk Management
3.1 Risk Terminology| Term | Definition |
| Threat | A potential danger |
| Vulnerability | Weakness that can be exploited |
| Risk | Likelihood of a threat exploiting a vulnerability |
| Mitigation | Reducing the impact of risk |
| Type | Description |
| Qualitative | Subjective risk evaluation (e.g., high, medium, low) |
| Quantitative | Uses numerical values (e.g., $$ impact) |
| Factor | Example |
| Something You Know | Password, PIN |
| Something You Have | Smart card, Token |
| Something You Are | Biometrics (Fingerprint, Retina scan) |
| Somewhere You Are | Geolocation-based access |
| Something You Do | Typing patterns, Gait recognition |
| Model | Description |
| MAC (Mandatory Access Control) | Strict access control (Used in military) |
| DAC (Discretionary Access Control) | Owner controls access (Used in small businesses) |
| RBAC (Role-Based Access Control) | Access based on job role |
| ABAC (Attribute-Based Access Control) | Access based on multiple attributes (Time, Location) |
- Use Multi-Factor Authentication (MFA).
- Enforce Least Privilege (Users get minimal access required).
- Regularly review access permissions.
- Use strong passwords (12+ characters, mix of uppercase/lowercase, numbers, symbols)
5.Cryptography & PKI
5.1 Encryption Types| Type | Description | Example |
| Symmetric | Uses a single key | AES, DES |
| Asymmetric | Uses a public/private key pair | RSA, ECC |
| Hashing | One-way transformation | SHA-256, MD5 |
- Provides Integrity, Authentication, Non-Repudiation.
- Uses Asymmetric Encryption (Private key signs, Public key verifies)
| Component | Function |
| CA (Certificate Authority) | Issues digital certificates |
| CSR (Certificate Signing Request) | Request for a certificate |
| CRL (Certificate Revocation List) | Lists revoked certificates |
| OCSP (Online Certificate Status Protocol) | Checks certificate status in real-time |
6.Network Security
6.1 Security Devices| Device | Function |
| Firewall | Blocks unauthorized traffic |
| IDS (Intrusion Detection System) | Detects attacks |
| IPS (Intrusion Prevention System) | Blocks attacks |
| Proxy Server | Acts as an intermediary between user and internet |
- Use WPA3 (Stronger than WPA2, WEP).
- Disable WPS (Weak security mechanism).
- Change default SSID and passwords
7.Security Operations
7.1 Incident Response Steps| Step | Description |
| Preparation | Establish security policies, training |
| Identification | Detect potential incidents |
| Containment | Isolate affected systems |
| Eradication | Remove the threat |
| Recovery | Restore systems to normal |
| Lessons Learned | Document findings for improvement |
| Strategy | Description |
| Backup | Copies of data for recovery |
| RAID | Disk redundancy (RAID 1, RAID 5) |
| Hot Site | Fully operational alternate location |
| Cold Site | Empty facility ready for setup |
| BCP (Business Continuity Plan) | Ensures business operations continue |
8.Security Policies & Compliance
8.1 Security Frameworks| Framework | Purpose |
| NIST | Cybersecurity best practices |
| ISO 27001 | Information security management |
| COBIT | IT governance framework |
| Regulation | Description |
| GDPR | Data protection in Europe |
| HIPAA | Health data security in the U.S. |
| PCI-DSS | Protects credit card data |
9.Common Commands for Security+
Windows Commands
ipconfig /all # View network settings
netstat -an # Show active connections
tasklist # Display running processes
ifconfig # Show IP settings
nmap -sV 192.168.1.1 # Scan open ports
sudo john hash.txt # Crack password hashes
10.Security+ Exam Tips
- Understand concepts instead of memorizing.
- Use CompTIA Security+ practice exams.
- Know the differences between encryption types.
- Learn real-world security applications.
11.Security Fundamentals
CIA Triad| Principle | Description | Example |
| Confidentiality | Protects data from unauthorized access | Encryption, Access Control |
| Integrity | Ensures data is accurate and unaltered | Hashing, Digital Signatures |
| Availability | Ensures data is accessible when needed | Backups, Redundancy |
