Infosec Journey

The rapid adoption of microservices, mobile apps, and SaaS platforms has made APIs a prime target for attackers. Recent industry reports show that API-specific attacks now account for a significant portion of web application breaches. These attacks often exploit issues like broken authentication. They also exploit excessive data exposure and lack of proper rate limiting. In fact, 85% of organizations in Asia-Pacific reported at least one API-related security incident in the past year. The average cost per incident exceeded $500,000.

But how do traditional web request risks compare to API risks? And do you really need separate tools to handle web and API security? Let’s break it down.

Web Requests vs. API Requests: What’s the Difference?

A web request typically comes from a browser, initiated by a user interacting with a website. It often involves HTML forms, cookies, and session-based authentication.
An API request, on the other hand, is usually machine-to-machine. Consider a mobile app talking to a backend. Or think about microservices communicating within a SaaS platform. API requests are typically stateless, use JSON/XML payloads, and rely on tokens (like JWT or OAuth) for authentication.

Key differences:

• Web requests: User-driven, rendered in browsers, session/cookie-based, UI-centric.
• API requests: Machine-driven, data-centric, token-based, often expose backend logic and data directly.

Are the Security Risks the Same?

While there’s overlap (e.g., both can suffer from injection attacks), API risks are distinct and often more severe due to:

• Direct access to backend data and logic
• Higher automation potential for attacks
• Less visibility and documentation (shadow APIs)
• More complex authentication and authorization flows

Examples from the OWASP Top 10:

• Web: Cross-Site Scripting (XSS), Cross-Site Request Forgery (CSRF), SQL Injection
• API: Broken Object Level Authorization (BOLA), Excessive Data Exposure, Lack of Rate Limiting, Shadow APIs

Do You Need Separate Tools for Web and API Security?

Short answer: Not anymore.
Modern WAFs are now designed to handle both web and API traffic, providing unified protection and visibility. While specialized API security tools exist (and may be needed for highly complex environments), most organizations can address core risks with an advanced WAF that includes API-specific features

API Security Challenges (and How a WAF Handles Them)

Let’s look at some real-world API attack scenarios and how a WAF can protect you:

1. SQL Injection in APIs

Attack:
An attacker sends a crafted POST request:

jsonPOST /api/user
{
  "username": "admin' --",
  "password": "irrelevant"
}

If the backend concatenates this input into a SQL query, it could allow unauthorized access.

WAF Protection:

• Detects SQLi patterns in payloads and blocks the request.
• Enforces input validation (e.g., only alphanumeric usernames).
• Flags abnormal query patterns for review.

2. Broken Authentication or Credential Stuffing

Attack:
A bot tries thousands of login attempts against /api/login using stolen credentials.

WAF Protection:

• Detects and blocks automated login attempts (bot mitigation).
• Applies rate limiting per IP/user.
• Uses IP reputation and device fingerprinting to block known bad actors.

3. Cross-Site Scripting (XSS) via API

Attack:
A malicious script is submitted via an API:

jsonPOST /api/comments
{
  "comment": "<script>alert('XSS')</script>"
}

WAF Protection:

• Sanitizes or blocks malicious script content.
• Detects known XSS vectors in API payloads.
• Context-aware filtering (e.g., JSON body vs. query string).

4. Excessive Data Exposure

Attack:
A client requests /api/user/123 and the API returns sensitive fields like passwords or tokens.

WAF Protection:

• Masks or removes sensitive fields from responses.
• Enforces a positive security model (only allows safe, predefined fields).

5. Lack of Rate Limiting / DDoS on APIs

Attack:
An attacker floods /api/search with thousands of requests per second.

WAF Protection:

• Enforces rate limits per endpoint/IP.
• Detects and blocks volumetric attacks at the application layer.

6. Broken Object-Level Authorization

Attack:
A user tries to access another user’s data by changing the ID in the API call:
GET /api/user/456

WAF Protection:

• Flags and blocks unauthorized access attempts.
• Enforces custom rules so users can only access their own data.

7. Server-Side Request Forgery (SSRF)

Attack:
A request to /api/fetch?url=http://168.253.169.254/latest/meta-data tries to access internal cloud metadata.

WAF Protection:

• Only allows requests to whitelisted domains/IPs.
• Blocks requests targeting internal or sensitive endpoints.

Why Bundling API Security with Your WAF Is Essential

Bundling API security with your WAF isn’t just convenient—it’s a necessity in today’s threat landscape.
A modern WAF gives you:

• Centralized, automated, and consistent protection for both web and API traffic
• Unified logging and monitoring for compliance and incident response
• Real-time threat detection and rapid response to evolving attacks

Bottom line:
You don’t need two separate tools for most environments. Invest in a modern WAF with robust API security features—and stay ahead of attackers while simplifying your security operations

Security controls and products will continue to evolve and multiply. True protection ultimately comes down to sharp configuration. It also relies on efficient implementation and smart processes. It’s not merely about tool proliferation or normalization. It’s crucial to choose the right features and use them wisely to stay one step ahead.