Security breaches make headlines, damage reputations, and can destroy businesses. Yet most are preventable. The OWASP Top 10 represents the security community's consensus on the most critical web application security risks.
Injection Attacks
SQL, NoSQL, and command injection remain dangerous. Always use parameterized queries:
// SAFE: Parameterized query
const result = await db.query(
'SELECT * FROM users WHERE id = \$1',
[userId]
);Authentication Failures
Hash passwords with Argon2id, regenerate session IDs after login, implement rate limiting on authentication endpoints.
import { hash, verify } from '@node-rs/argon2';
const passwordHash = await hash(password, {
memoryCost: 65536,
timeCost: 3,
parallelism: 4
});XSS in the React Era
React's JSX escapes content by default, but beware dangerouslySetInnerHTML and URL-based XSS. Always sanitize HTML and validate URL protocols.
import DOMPurify from 'dompurify';
const sanitized = DOMPurify.sanitize(content, {
ALLOWED_TAGS: ['b', 'i', 'a'],
ALLOWED_ATTR: ['href']
});Security Misconfiguration
CORS misconfiguration, environment exposure, and default credentials are easy attack vectors. Be explicit about allowed origins and never expose secrets to client code.
Security Headers
// next.config.js
const securityHeaders = [
{ key: 'Content-Security-Policy', value: "default-src 'self'" },
{ key: 'X-Frame-Options', value: 'DENY' },
{ key: 'Strict-Transport-Security', value: 'max-age=31536000' }
];Security Checklist
Passwords hashed, sessions regenerated, rate limiting enabled, inputs validated, queries parameterized, HTML sanitized, CSP configured, HTTPS enforced, no secrets in client code.
Security isn't a feature you add—it's a practice you maintain. Your users trust you with their data. Honor that trust.