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Beginner Security

Web Security Fundamentals

Common vulnerabilities and basic protection strategies.

Security Mindset

Security isn't a feature—it's a process. Understanding common threats helps you build safer applications.

Core Principles

  • Defense in Depth: Multiple layers of security
  • Least Privilege: Minimal necessary permissions
  • Fail Securely: Deny by default on errors
  • Trust No Input: Validate everything

Common Vulnerabilities

  • XSS: Injecting malicious scripts
  • CSRF: Forged cross-site requests
  • SQL Injection: Malicious database queries
  • Broken Auth: Session/token flaws

Quick Wins

  • Use HTTPS everywhere
  • Keep dependencies updated
  • Hash passwords with bcrypt/Argon2
  • Set security headers (CSP, HSTS)
  • Validate and sanitize all input

Security Headers

Content-Security-Policy: default-src 'self'
Strict-Transport-Security: max-age=31536000
X-Content-Type-Options: nosniff
X-Frame-Options: DENY