Top 7 Steps to Secure Your API from Common Attacks

First, you must understand that securing your API is not something to take lightly! That’s why you need to know how to protect your APIs properly — and in this article, we’ll summarize the 7 most important steps to do so.

Rate Limiting

One of the most important steps in protecting your API is rate limiting. Without limits, anyone can flood your API with massive amounts of requests — causing DDoS attacks or Brute-force attempts.
It’s best to define request limits:

• Per IP

• Per User

• Per Endpoint

That way, you prevent abuse and maintain API stability.

Access Control via CORS

CORS defines which domains are allowed to send requests to your API.
If you leave it open to any domain (*), a malicious site can send requests on behalf of logged-in users — exposing their data to potential theft.
Always restrict access to trusted domains only to ensure security.

Protection from SQL & NoSQL Injection

One of the biggest API threats is database injection, which happens when user input is inserted directly into queries without validation.
To prevent this:

• Use Prepared Statements, ORM, or Parameterized Queries.

• Always perform Input Validation & Sanitization before using user data in queries.

This way, attackers can’t inject harmful SQL or NoSQL commands into your database.

Web Application Firewall (WAF)

Having a WAF such as AWS WAF or Cloudflare WAF adds an extra layer of protection for your API.
A WAF can:

• Filter suspicious requests before they reach your app.

• Block common attack patterns like SQL Injection and XSS.

• Reduce security incidents and improve service stability.

This makes your API more resilient and not solely reliant on code-level security.

VPN or Internal Network

Some APIs — especially for admin panels or reports — shouldn’t be public.
To secure them:

• Place them within a private network or behind a VPN.

• Restrict access to an IP Allowlist (only specific trusted IPs).

This ensures only authorized users can reach sensitive endpoints, minimizing risks.

Protection from CSRF (Cross-Site Request Forgery)

If a user is logged in, a malicious website could exploit their session to perform unwanted actions on your API.
To protect your API:

• Use CSRF Tokens for all state-changing requests (POST/PUT/DELETE).

• Verify the token’s validity with every request before performing the operation.

This prevents external sites from sending unauthorized requests and keeps user sessions secure.

Protection from XSS (Cross-Site Scripting)

If your app displays user-generated content, attackers could inject malicious JavaScript.
To protect your API and users:

• Always Escape or Sanitize user inputs before displaying them.

• Implement a Content Security Policy (CSP) to restrict script execution.

This prevents attackers from stealing cookies or executing malicious scripts via your API or UI.

Final Tips & Best Practices

Don’t rely on a single security layer. For a truly secure API:

• Combine WAF, Rate Limiting, Input Validation, and Monitoring.

• For critical APIs, place them behind a VPN or IP Allowlist.

• Continuously monitor Logs and Metrics; sudden Latency spikes or high Error Rates could indicate attacks or performance issues.

Following these best practices significantly reduces risk and ensures your API stays stable and secure.