What is API Security Testing: The Ultimate Guide for your Business Growth

Illustrator: Adan Augusto
What is API Security Testing

APIs or Application Programming Interfaces are an ever-present element of modern software development, and it follows that they're a potentially massive liability as well. Faulty API security could allow malicious third parties to gain access to critical application functions and sensitive data, meaning that they're a potential goldmine for those seeking to exploit any security vulnerabilities that may provide the opportunity to do so.

It also follows, then, that API security testing is an increasingly important part of the process of developing and deploying secure applications like chatbots in this day and age. Without APIs, it would be far more difficult to efficiently develop and deploy contemporary applications and applets, especially if the given feature set describes meta-application interactions and other advanced functionality. Furthermore, companies often use APIs to safe-keep their most important data. This means that API security testing is absolutely paramount if the developer wishes to protect their code from attacks and ensure a long-lasting baseline of security.

This article aims to explore the basics of API security testing. It will also go over some additional information, such as the importance of choosing the right API security testing tools, as well as a comprehensive suite of API security tests that should be put into place for optimum results.

What is API Testing?

In broad, generalized terms, API security testing is a type of software composition analysis that focuses mainly on verifying the functionality, performance, and security of a given API. API security testing is a kind of black-box analysis, in that the test cases are generally designed without the knowledge of the internal structure of the application that is being tested.

API security testing is a critical part of the software development life cycle. It involves the testing phase of an application's programming interfaces directly and as a part of the provided integration testing. Running these tests helps determine whether the given API meets the three separate sets of expectations that were outlined in the previous paragraph.

It is self-explanatory that API testing is an absolutely crucial part of developing a robust software application. Running API testing is the only way to verify whether the API meets the needed requirements of security and performance, and it's a stellar way of checking for any potential errors, bugs, and vulnerabilities ahead of an application's official release. This means it's also reasonably cost-effective in the grand scheme of things.

Different Types of API Security Testing

Typically, developers will leverage both manual and automated testing to assess their API security systems. Sometimes, this means using specialized tools, while other times it may be as (relatively) simple as pushing out a custom stressor across their API routes. Functional tests vary in efficiency and specialization, and maintaining API security may mean two entirely different things in different contexts, meaning that new and inventive security tests are being designed all the time.

Naturally, it is possible to run certain standardized SAST (static application security testing) and SCA (software composition analysis) tools to check if they discover any potential API usage issues, but it is recommended that developers don't rely purely on these solutions. Instead, something a tad more specific and specialized might be needed: dynamic API security testing.

API endpoints need to be checked through the use of up-to-date (and fully supported, mind you!) dynamic AST security tests, which simulate a real-world use case and realistic attack scenarios. This, in turn, helps draw out any potential vulnerabilities that may not have been uncovered by static API security testing.

Security and development teams that wish to bolster their API security as much as possible, and want to come up with an exhaustive set of security testing tools, should use DAST as a baseline. Then, the established dynamic security testing scenarios can be bulked up through the use of additional SAST and SCA processes.

User Authentication Mechanisms Come Into Play, Too

On top of basic API security testing, it's also worth remembering that an API itself doesn't exist in a vacuum. Users and clients are a crucial part of any forward-facing API, and developers that take security seriously ought to invest in client-certificate authentication at some point. If the API is used on a website, securing the right Secure Sockets Layer from a digicert reseller for the site is key.

Note that the fact that an API has been tested for security doesn’t mean users shouldn’t be proactive in helping prevent attackers from gaining access to their own sensitive data. So, those accessing banking sites can also use a credit monitoring service to detect signs of fraud, for example. Identity theft protection services can also help.

Key Elements of API Security Testing

The deployment method and configuration of API security testing can vary depending on the specific tools and techniques being used, as well as the requirements and constraints of the system that is being tested. In general, however, the deployment of API security testing typically involves the following steps:

  1. Identification of testing tools and techniques: The first step in deploying API security testing is to identify the tools and techniques that will be used. This typically involves reviewing the available tools and techniques, as well as selecting those that are most appropriate for the specific API and system being tested.
  2. Configuration of the testing environment: The next step is to configure the testing environment. This typically involves setting up a separate testing environment that is isolated from the production environment and configuring the testing tools and any test data that will be used.
  3. Testing phase: Once the testing environment is set up, the next step is to conduct the tests. This typically involves using a combination of automated and manual testing techniques to identify potential vulnerabilities in the API.
  4. Analysis of the test results: After the tests have been completed, the next step is to analyze the test results. This typically involves reviewing the results of the tests to identify any vulnerabilities or weaknesses and determining the potential impact of these vulnerabilities on the API and the overall system.

The specifics will, naturally, vary depending on a wide variety of different API features, but the broad approach will apply almost across the board. API security tests run the provided web applications, API routes, and API calls through the wringer, which means that they're a solid way of doing performance testing as well. If your implementation holds up to comprehensive API security tests without problems, your application backend is on the right track!

Choosing the Right API Security Testing Tools

There's a huge number of different API security testing tools available on the market right now. Not all of them will be appropriate for every use case, and not all of them will be able to provide proper security coverage in all the important contexts. In other words, being able to discern how specific API security testing works will be all the difference between the deployment of secure APIs and risking your data for no good reason.

The first step in this regard will be to assess the API you're trying to test, and the sort of web applications it's supposed to run within. Take into account all of the API’s disparate features and configuration details, and then consider the API tests themselves. Developers looking into API tests should take note of the following:

  • API support (SOAP, GraphQL, REST, etc.)
  • Testing configuration (API routes vs. blind crawling)
  • Deployment method
  • Performance testing effects
  • Scanning technology and quality
  • Scanning accuracy (false positives are a serious concern)
  • Customization capacity

Since different API security testing tools are built for different ways of testing APIs, finding the right fit for your specific use case might be easier said than done. Often, the choice will boil down to deciding whether it's more necessary to automate testing or to afford total customization for specific API scanning setups, for example.

It's always worth remembering that continuous testing will eventually help uncover most API security issues in the long run. Especially for security teams that end up investing in several different testing tools all at once. For those who are pressed for time and/or money, however, choosing critical aspects of the API in question to focus on will be the way to go.

Conclusion: The Importance of API Security Testing

API security testing is a crucial element of modern application architecture development. APIs are a critical part of the modern version of the Web, and API vulnerabilities have the potential to cause immense mayhem if they're not treated with respect for security issues.

In summary, API security testing helps to identify any vulnerabilities or weaknesses in an API that could be exploited by attackers and provides recommendations for addressing these vulnerabilities. This can help to prevent attackers from gaining access to sensitive data or functionality, and can help protect the overall system from potential security threats.