Web Application Security Essentials

Security should never be an afterthought. This guide covers the most critical security practices every web developer should know.

OWASP Top 10 Threats

  • SQL Injection - Always use parameterized queries
  • XSS (Cross-Site Scripting) - Sanitize all user input
  • CSRF - Use anti-CSRF tokens in forms
  • Broken Authentication - Implement proper session management

Security Headers

# Nginx security headers
add_header X-Frame-Options "SAMEORIGIN";
add_header X-Content-Type-Options "nosniff";
add_header X-XSS-Protection "1; mode=block";
add_header Strict-Transport-Security "max-age=31536000";

Best Practices

Use HTTPS everywhere, implement rate limiting, keep dependencies updated, and regularly audit your code for vulnerabilities. Enable 2FA for admin accounts and use environment variables for secrets.