How to secure a Node.js application

· Category: Node.js

Short answer

Secure Node.js apps by validating input, using HTTPS, setting security headers with Helmet, managing secrets properly, and auditing dependencies.

Steps

  1. Install Helmet: npm install helmet; use app.use(helmet()); to set secure headers.
  2. Validate all user input with libraries like joi or zod.
  3. Use parameterized queries or ORMs to prevent SQL injection.
  4. Store secrets in environment variables, never in code.
  5. Run npm audit regularly and update vulnerable packages.

Tips

  • Enable rate limiting to mitigate brute force and DDoS attacks.
  • Use express-rate-limit and cors appropriately to restrict access.

Common issues

  • Default Express configurations expose the X-Powered-By header, which Helmet removes.
  • Deserializing untrusted data with eval or new Function creates remote code execution risks.