Securing REST & GraphQL APIs Against Modern Cyber Threats

The Growing Criticality of API Security

APIs are the engine of modern web and mobile applications. As web applications shift towards decoupled client-side rendering and mobile frontends, securing API endpoints becomes synonymous with securing the entire platform.

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1. Authentication & JWT Token Best Practices

JSON Web Tokens (JWT) are widely used for stateless authentication, but implementation flaws can lead to severe security breaches.

• Short-Lived Access Tokens: Keep access token lifespans short (15 to 30 minutes). Use secure, HTTP-only refresh cookies to issue new access tokens seamlessly.
• Never Store Tokens in LocalStorage: LocalStorage is vulnerable to XSS attacks. Store sensitive tokens in SameSite=Strict, HttpOnly, Secure cookies.
• Validate Token Algorithms: Reject tokens using the "alg": "none" signature algorithm exploit by strictly enforcing asymmetric signing algorithms like RS256 or ES256.

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2. Granular Rate Limiting & DoS Protection

Unprotected APIs can be overwhelmed by bot traffic or abused for price scraping and credential stuffing.

• IP-Based & User-Based Rate Limits: Rate limit requests based on authenticated user IDs as well as client IP addresses to prevent distributed bot evasion.
• Tiered Endpoints: Apply strict rate limits to sensitive routes (login, password reset, payment processing) while allowing higher limits for read-heavy public APIs.

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3. Defensive Schema Validation

Never trust data incoming from client payloads. Unvalidated inputs lead to SQL injection, NoSQL injection, and application crashes.

• Schema Validation: Define strict validation schemas using libraries like Zod or Joi. Reject unexpected fields automatically.
• Sanitize Data Output: Ensure internal database fields (such as hashed passwords, reset tokens, or internal flags) are stripped from API responses prior to returning them to clients.