Security Is Not Optional

Web application security is not a feature — it is a foundational requirement. Every web application is a target for automated attacks, and a single vulnerability can compromise customer data, damage reputation, and incur regulatory penalties. At Nexis Limited, security is integrated into our development process from design through deployment.

Authentication Best Practices

  • Use established libraries: Never roll your own authentication. Use battle-tested solutions like NextAuth.js, Passport.js, or Django's authentication system.
  • Hash passwords with bcrypt or Argon2: These algorithms are designed to be computationally expensive, making brute-force attacks impractical. Never store passwords in plain text or with fast hashing algorithms like MD5 or SHA-256.
  • Implement Multi-Factor Authentication (MFA): MFA adds a second verification step that dramatically reduces the risk of account compromise even if passwords are leaked.
  • Use JWTs wisely: Store JWTs in HttpOnly, Secure, SameSite=Strict cookies rather than localStorage. Keep token expiration short (15 minutes) and use refresh tokens for session continuation.

Authorization and Access Control

Authentication verifies who you are; authorization verifies what you can do. Our Bondorix platform uses role-based access control (RBAC) with approximately 70 fine-grained permissions across 8 roles. Key practices:

  • Default to deny — users have no permissions unless explicitly granted.
  • Enforce authorization on the server side, never rely solely on client-side UI hiding.
  • Use Row-Level Security in PostgreSQL as a database-level safety net.
  • Audit all permission changes and access to sensitive resources.

Input Validation and Sanitization

All user input is potentially malicious. Validate and sanitize on the server side regardless of client-side validation:

  • Use parameterized queries or ORMs to prevent SQL injection.
  • Sanitize HTML output to prevent Cross-Site Scripting (XSS).
  • Validate file uploads — check MIME types, file size, and scan for malware.
  • Reject unexpected fields in API requests to prevent mass assignment vulnerabilities.

HTTPS and Transport Security

HTTPS is mandatory, not optional. Use TLS 1.3, configure HSTS headers, and redirect all HTTP traffic to HTTPS. Obtain certificates from Let's Encrypt for free automated certificate management.

Security Headers

Configure these security headers on every response:

  • Content-Security-Policy: Restricts which sources can load scripts, styles, and other resources.
  • X-Content-Type-Options: Prevents MIME type sniffing.
  • X-Frame-Options: Prevents clickjacking by controlling iframe embedding.
  • Referrer-Policy: Controls how much referrer information is shared with external sites.
  • Permissions-Policy: Controls browser feature access (camera, microphone, geolocation).

Dependency Security

Third-party dependencies are a common attack vector. Audit dependencies regularly with tools like npm audit, pip-audit, or govulncheck. Pin dependency versions in production, and update promptly when security patches are released. Use Dependabot or Renovate for automated dependency updates.

Conclusion

Web application security is a continuous practice, not a one-time checklist. Integrate security into your development workflow, automate security scanning in CI/CD, and stay informed about emerging threats. The cost of prevention is always lower than the cost of a breach.

Need a security audit for your web application? Contact our team for a comprehensive assessment.