API Penetration Testing

Secure Your REST and GraphQL APIs

Comprehensive API security assessments including OWASP API Security Top 10 testing, authentication, authorization, and injection vulnerability analysis.

What Is API Penetration Testing?

API penetration testing is a comprehensive security assessment of your application programming interfaces, including REST APIs, GraphQL APIs, SOAP services, and custom API implementations. We simulate real-world attacks against your APIs to identify authentication weaknesses, authorization bypass vulnerabilities, injection flaws, excessive data exposure, rate limiting issues, and other security gaps. API testing is critical because modern applications rely heavily on APIs for internal communication, third-party integrations, and mobile app functionality, making API security essential to overall application security.

Why API Testing Matters

Increasing API Usage

Modern applications are built on APIs. Mobile apps, third-party integrations, and microservices all depend on APIs. As API usage grows, so does the attack surface for compromising applications.

Hidden Data Exposure

APIs often expose more data than web interfaces due to insufficient filtering or overly permissive responses. Testing reveals where sensitive data is accessible through API endpoints.

Authentication & Authorization Gaps

Many APIs have inadequate authentication mechanisms or authorization checks that allow attackers to access resources belonging to other users or escalate their privileges.

Business Logic Vulnerabilities

APIs implement complex business logic that may contain flaws enabling unauthorized transactions, data manipulation, or privilege escalation not possible through the web interface.

What We Test

REST APIs

RESTful API security including HTTP method vulnerabilities, endpoint enumeration, and resource-based access control flaws.

GraphQL APIs

GraphQL-specific vulnerabilities including introspection queries, excessive data exposure, injection attacks, and query complexity exploitation.

OWASP API Top 10

Comprehensive testing for broken object level authorization, broken authentication, excessive data exposure, lack of resources and rate limiting, and broken function level authorization.

Authentication & Authorization

API authentication mechanisms (OAuth 2.0, JWT, API keys), token validation, session management, and access control enforcement.

Injection Attacks

SQL injection, NoSQL injection, command injection, and other injection vulnerabilities through API parameters and request bodies.

Rate Limiting & Resource Limits

Testing for adequate rate limiting, resource quotas, request size limits, and protection against brute force and denial-of-service attacks.

Our API Testing Methodology

1. API Reconnaissance & Enumeration

We discover and document all API endpoints, parameters, request/response structures, authentication mechanisms, and available functionality through API documentation, inspection, and active testing.

2. Authentication & Authorization Testing

We test authentication implementation, attempt token manipulation, test authorization controls, check for privilege escalation paths, and validate proper access control enforcement.

3. Input Validation & Injection Testing

We test for SQL injection, NoSQL injection, command injection, path traversal, and other injection vulnerabilities through various API parameters and payloads.

4. Data Exposure & Business Logic Testing

We attempt to access resources belonging to other users, extract excessive data through API responses, manipulate business logic, and exploit API-specific vulnerabilities.

5. Comprehensive Reporting & Recommendations

We provide detailed findings with proof-of-concept demonstrations, prioritized recommendations, remediation guidance, and architectural improvements for API security.

API Penetration Testing Pricing

AI-Assisted Assessment

$500

Automated API security assessment with AI-powered vulnerability scanning. Ideal for single API endpoint analysis and initial vulnerability discovery.

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Manual API Testing

$2,000+

Comprehensive manual penetration testing by certified professionals. Covers REST, GraphQL, OWASP API Top 10, authentication, authorization, and business logic vulnerabilities.

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Compliance & Standards Coverage

PCI DSS

Payment Card Industry Data Security Standard compliance testing for APIs handling cardholder data and payment information.

HIPAA

Healthcare Industry compliance testing for APIs protecting patient health information and medical records.

SOC 2 Type II

Service Organization Control compliance validation for API security, availability, and confidentiality controls.

ISO 27001

International information security management standard compliance for API infrastructure and security controls.

NIST Cybersecurity Framework

National Institute of Standards and Technology framework alignment for API security maturity assessment.

CMMC 2.0

Cybersecurity Maturity Model Certification compliance for defense contractors using APIs for defense-related work.

Frequently Asked Questions

What types of APIs do you test?

We provide comprehensive penetration testing for REST APIs, GraphQL APIs, SOAP web services, gRPC services, and custom API implementations. Our testing methodology applies to any API architecture.

What is the OWASP API Security Top 10?

The OWASP API Security Top 10 lists the most critical API vulnerabilities including broken object level authorization, broken authentication, excessive data exposure, lack of resources and rate limiting, broken function level authorization, mass assignment, and other API-specific security risks.

How do you test APIs without disrupting service?

We work with your team to test against staging or sandbox environments. Our testing focuses on identifying vulnerabilities through request analysis and manipulation rather than denial-of-service attacks that would disrupt service.

What vulnerabilities are most common in APIs?

Common API vulnerabilities include broken authentication, inadequate authorization checks, excessive data exposure through error messages, lack of rate limiting, insecure direct object references, injection flaws, and insufficient input validation.

Do API tests help with compliance?

Yes, API penetration testing supports compliance with PCI DSS, HIPAA, SOC 2 Type II, ISO 27001, NIST Cybersecurity Framework, and CMMC 2.0 requirements by validating secure API design and implementation.

Related Services

Web Application Testing

Comprehensive web application security assessments including frontend and backend vulnerabilities.

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External Penetration Testing

External-facing infrastructure and API assessment from an attacker's perspective.

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Network Penetration Testing

Network security assessments including infrastructure testing that APIs depend on.

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Ready to Test Your API Security?

Contact us today for an API penetration testing consultation and comprehensive security assessment.

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