What is API security testing?

API security testing is the process of assessing an API’s security in order to detect and fix vulnerabilities, errors, bugs, etc. It helps protect APIs from cybersecurity risks like data breaches, unauthorized access, DDoS attacks, injection attacks, and more. 

This process involves checking the API’s endpoints for potential security issues and ensuring secure data transmission. It also ensures that the API meets defined security requirements and follows best practices. 

Conducting API security testing systematically allows organizations to uphold an API’s integrity and performance. API security testing evaluates an API’s input validation processes, authorization and authentication mechanisms, error handling, and other security-related areas. It enables them to find potential security vulnerabilities, threats, and risks and fix them quickly before they convert into an attack. 

Types of API Security Testing

• Static API security tests: SAST helps you detect security issues in your API by evaluating its source code. 
• Dynamic API security tests: DAST involves checking the API’s security by sending simulation requests mimicking real-world attacks like SQL injection, tampering testing parameters, fuzzing inputs, entering random data, etc. 
• SCA: Software composition analysis (SCA) detects known vulnerabilities in the frameworks or libraries used in the API. 

Today, organizations utilize advanced API security testing solutions like Appknox’s SAST, DAST, and API scanners to secure their endpoints and prevent attacks. 

Why should you perform API security testing?

APIs not only offer more connected experiences by exchanging data between apps but also house sensitive data that malicious actors can hack. Here are common security vulnerabilities in APIs: 

• Injection attacks: Hackers inject malicious code into API requests to access unauthorized data, takeover accounts, or compromise systems. 
• DDoS attacks: Attackers flood an API’s infrastructure with too many requests at a time to make the API unresponsive and disrupt services. 
• Broken authentication and access controls: Weak access controls, authentication mechanisms, and session management can lead to access control vulnerabilities, enabling attackers to hijack sessions and access sensitive data. 
• Insecure Direct Object Reference (IDOR): With weak authorization, attackers manipulate API’s internal references like file paths, database IDs, etc. 
• Lack of rate limiting: Rate limiting lets you control how many requests an API can process in a specific timeframe. With no rate limiting in the API, attackers can overload the system with excessive requests, resulting in service outages and data loss. 

Other API vulnerabilities include cross-site scripting attacks, HTTP vulnerabilities, input validation issues, etc. 

API security testing aims to address the above vulnerabilities by scanning for issues and allowing you to fix them in time. It offers the following advantages:

• Improved API security: Performing API security tests in the early stages of SDLC allows you to detect and remove vulnerabilities proactively. This helps protect your API and sensitive business data from unauthorized access.  
• Operational efficiency: Resolving security issues on time helps prevent service outages due to cyberattacks, without affecting operations. 
• Reduced compliance risks: Securing business and customer data keeps you audit-ready and enables you to meet compliance requirements confidently. 
• Customer trust: Conducting API security testing to protect data shows your commitment to customer experience and helps gain their trust and loyalty. 

What are some key API vulnerabilities?

Security issues and Vulnerabilities in APIs typically fall into a few distinct categories. Some of the key API vulnerabilities include:

1. Access Control Vulnerabilities

Authentication: Similar to how doors have multiple types of locks, APIs can have several authentication mechanisms. API keys supplied as headers or query parameters, HTTP Basic Authentication using a username and password, and OAuth 2.0 Bearer Access Tokens are all common authentication methods.

Authorization: Authorization is the process of figuring out if a user or machine can access data or do actions with or without authentication. Access control policies and privileges can be used together to make this happen. Authorization is a bit harder to set up than authentication because it requires setting up complex chains of multiple rules and policies that must be evaluated securely to allow or block actions.

Access control policies frequently have a pattern. When a client requests access to a resource that needs authentication, the server examines the request for authorization and authentication and looks for items like:

• If the account is present
• Whether the requested resource falls under the client's access scope
• If the request included any cookies or tokens from the past, etc.

The server may return a token, session id, or other identifiers to mark the session if the attempt is successful. Throughout the session, additional authenticated requests will proceed similarly.

2. Input Validation

Input validation is always essential to consider while searching for bugs in your API. Understanding that input includes everything the server receives from the user, third-party applications, and internal procedures are vital. Common areas to test for input attack vectors in an API include:

• Within the requested header
• Parameters within the request
• Parameters within the URL
• Different request methods
• File uploads (PUT/DELETE requests)

3. Rate Limiting Vulnerabilities

APIs are designed for applications anticipating a high volume of random requests. This feature can be exploited to enumerate the API endpoints in unforeseen ways rapidly. If an API's rate limiting isn't set up right, it could be used to send a lot of requests to enumerate the application and cause other issues.

4. HTTP Vulnerabilities

APIs support a variety of HTTP methods. When testing the API, it's crucial to understand what the application expects and what it supports. Sometimes using HTTP methods can force a user to execute prohibited operations like PUT, POST, DELETE, etc. Even if these are not incorporated into the application logic, bizarre things can happen if the program is sloppy and lacks any logic to parse.

5. Cross-Site Scripting Attacks

Cross-site scripting, or XSS, occurs when malicious code is inserted into a website. These codes have the power to force the user to take any action, including unauthorized access and data breaches. The attacker's intentions will wholly determine its actions.

6. SQL Injection

In this vulnerability, a user enters a SQL query instead of valid data, which can change the way your API works.

How to perform API security testing?

Define Testing Scope 

To ensure a focused and effective API security testing process, define your testing requirements. 

Figure out which endpoints and APIs to include that may have potential vulnerabilities. Categorize endpoints based on data sensitivity, security risks, and functionality. 

Set Up a Test Environment

Set up an isolated test environment dedicated only to API security testing to gain more accurate results. This environment must be a close replica of your API production environment with similar configurations like network architecture, server setups, etc. 

You can also utilize virtualization technologies such as containers like Docker or virtual machines (VMs) for higher scalability and efficiency. 

Gather Resources and Tools

Using efficient API security testing tools helps you automate the process and save time. It also minimizes the risk of human-led errors and aids in documentation and reporting. 

API scans, SAST, DAST, and penetration testing by Appknox allow you to identify vulnerabilities in under 60 minutes. We support 7+ compliance regulations, 140+ test cases, and detailed reports with less than 1% false positives. 

In addition, understand popular security testing frameworks like OWASP API Security Top 10 vulnerabilities to resolve issues faster. Review API specifications and documentation to know how an API behaves under a given circumstance, as well as security measures, test cases, etc.  

Test for Authentication and Authorization

• Inspect the API’s authorization and authentication mechanisms using user credentials, API keys, MFA, etc. Find out who all have sensitive data access. 
• Test authorization controls by analyzing privilege escalations, unauthorized data access, bypassed authorizations, etc. 
• Examine configurations and access control rules  
• Analyze the API’s input handling capability to mitigate vulnerabilities like cross-site scripting, SQL injections, etc., and verify data integrity. 
• Check error handling capabilities by testing API responses to various error conditions. 
• Find out exception management capabilities of API in scenarios like DDoS attacks. 

In addition, implement mechanisms like rate limiting, throttling, etc. to prevent API abuse and DDoS attacks.

What is the Timeline for API Security Testing?

Ideally, the time required for API security testing< depends on the project's scope and infrastructure. Depending on the number of test cases, the time can vary from a few hours to a few days. If you are going for the Appknox Mobile App Security Testing suite, the entire process will finish in less than 60 minutes with more than 130+ test case coverage and less than 1% false positives!

How Much Does API Security Testing Cost?

To have a secure website, you need to find the right API security testing provider that can find all your API's hidden flaws. Depending on the size and complexity of an API security test, the price might range from $500 to $6,000 per scan. However, several customized plans are available in the market, which caters to your application specifically, and the price is decided flexibly. 

The most popular Appknox Profesional testing plan, which offers unlimited vulnerability assessment and dedicated call and chat support, comes at unbelievably affordable prices!

API security testing:  Best practices 

Follow the below security practices to protect your APIs:

• Continuous monitoring and testing: Monitor and test your APIs continuously to keep detecting and removing new security vulnerabilities introduced after changes or updates. 
• Stay informed: Staying informed with the latest security practices and threat landscape will help you remove threats faster and improve security organization-wide. 
• Meet compliance: Compliance requirements change rapidly, so keep up with them to avoid penalties. Also, follow security guidelines and standards like OWASP to apply proper security controls. 
• Leveraging advanced tools: Use advanced security tools and technologies to automate API testing, save time, and remain one step ahead of cyber attackers. 

Protect Your APIs and Data with Appknox’s API Scans

API security testing enables you to ensure your API is free from security vulnerabilities, keeping attackers at bay. 

Using advanced API scans by Appknox can help you detect vulnerabilities in a minute to secure your APIs and endpoints. We support 140+ test cases so you can test your API for a variety of scenarios with less than 1% false positives. You’ll also get a detailed vulnerability assessment report with a CVSS score to understand business impacts. 

Scan Your API for Vulnerability and Stay Secure!

FAQs

Q. What’s the timeline for API security testing?

A. API security testing may take a few minutes, hours, or days based on the testing scope and organization size. Automated API security testing tools help reduce this timeline.

Q. How much does API security testing cost?

A. Based on the security service provider and testing complexity, the cost of API security testing may vary from a few hundred dollars to a few thousand dollars per scan ($350-$6000. Appknox offers accurate vulnerability assessments for APIs at affordable rates. Contact the team for a quote based on your unique requirements. 

Q. Is API testing easy or tough?

A. API testing is simple. Use an automated API security testing solution like Appknox and scan your API for vulnerabilities in under 60 minutes. Our expert security researchers run penetration testing, consolidate reports, and recommend remediation.