API Security Testing

Getting Started: API Security Testing Overview

For attackers, APIs offer an important attack surface. They generally feature comprehensive instructions regarding obtaining this kind of access, in addition to being designed for granting permission to confidential data and essential program features. They are an exclusive online resource that provides attackers with an exact, detailed manual for launching an assault. SDLC programs, teams working on AppSec and product safety, and quality control procedures must all incorporate API safety inspections for the aforementioned purposes.  

An API is examined during an API safety evaluation procedure to ensure security. In contrast to app safety assessment, API verification searches for hidden flaws and confirms the integrity of data transmitted and obtained through the API. 

Additionally, it could entail ensuring that the API is free of dangerous malware and is not accessible to outside parties. Since the software is continuously being compromised and illicit actors have ways to exploit app vulnerabilities to gain mission-critical data, API security evaluation is a crucial component of developing software nowadays. There are countless security risks with APIs.

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Why is testing vital for securing an API?

As previously stated, API enables the transmission of information between apps. A malicious individual who compromises the privacy of your API may obtain confidential information kept on your web page.

Additional unpleasant effects of an API safety compromise include:

• Loss of client data/privacy. (What if it reaches the dark web and is sold there?)
• An attack on your web page and business. It may negatively impact both your standing and your company.
• Both user count and income decline.
• Litigation (if you are negligent).

Many apps' core functionality is driven by APIs, which give programmers strong access points to a company's offerings. For a business to be generally secure, APIs must adhere to stated requirements and resist unreliable and possibly harmful information.

APIs are not covered by conventional dynamic application safety testing (DAST) analyzers; they are only partially covered. Conventional DAST analyzers cannot detect API endpoints if a company's front end has no interaction with them. Thus, it is crucial to implement a current, adaptive API security assessment approach focusing on problems across each API's output.

How it works?

Multiple kinds of API inspections exist. Your code source may contain trends and resources that signify potential weaknesses. 

The static evaluation and system compositional assessment look for such trends and archives, uncovering the susceptible program or module. Interactive API inspections deliver ongoing queries to the program, disclosing potential risks depending on the API reaction.

For instance, a query made to a REST API route that supports SQL Injection might be sent by an interactive monitoring tool. The validation tool would come up with this information if a reply from the API were obtained, and it suggested that the database's integrity was open to an attack.

This kind of privacy assessment is sometimes referred to as an " adverse safety assessment" because it involves sending an inquiry and verifying if it obtains a response.

Advantages of using API Security Testing

Standard API safety checks assist in locating and preventing weaknesses and the possibility of organizational risk they pose. 

In particular, API safety verification is tailored to the API being evaluated, as well as an organization's general approach and best practices. The APIs used by single-page web apps, IoT solutions, or smartphone apps are examined by API analyzers at a more advanced level. API analyzers can snoop through information sophisticatedly to find concealed vulnerabilities by knowing what an API wants as input.

API security testing tools also assist in enforcing an API's accuracy by examining the company's functionality of an API as opposed to just the data input validation done at the app’s frontend.

Finding areas where an API deviates from public API guidelines can also be done with API security assessments. For instance, auditors will notify the correct stakeholder when a certain route is expected to reply with one HTTP status indicator but instead returns a different one. This makes it possible to guarantee that the programmers who employ the APIs receive a user interface that adheres to stated guidelines.

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Types of API Security Tests

These are the major types of API safety evaluations:

FAST - Framework for Automated Security Testing

Without investing much effort, you can significantly expand the scope of safety tests. FAST generates and executes 1000 times safety checks dynamically for each functional test using its fuzzer and existing vulnerability injectors. There are many distinctive characteristics in Wallarm’s FAST that may assist teams working on DevOps in managing the app's safety with short turnaround cycles. Wallarm also offers a product - API Security Platform

DAST - Dynamic Application Security Testing

Carrying out live (dynamic) checks against your API terminals is considered the most optimal method for evaluating an API, even if a few SAST and SCA tools include support for APIs. Although theoretically a type of DAST, vigorous testing should be avoided when using older DAST resources not designed for APIs. 

A real-time API security analysis replicates a real-life assault. It identifies flaws generated by both the software you and your teammates built and its reliance on open-source libraries. 

Integrating dynamic evaluation with SAST and SCA would be perfect if you were trying to create the most trustworthy API security assessment method. However, if you're searching for the ideal starting point to protect your APIs, DAST is the best method.

SAST - Static Analysis Security Testing

SAST is a method of software evaluation that inspects if there exist security flaws in the program's underlying code.

A form of CASE tool, static evaluation, examines source code without running it. In a program or system's source code, it can be employed to find programming mistakes, shortcomings in the design, and safety holes.

Software Composition Analysis (SCA)

SCA is a method used in software development that aids in locating software elements and their connections. It may be employed to assess an app's design, spot problematic software, or determine the amount of code required for a specific activity.

Authentication

To gain entry to an environment, assistance, or network, verification is a way to validate a user's or device's existence. Every app needs to authorize users, and several different methods are used for it, including login and password verification, multi-factor authentication, and API authorization.

An API password is used to confirm an individual's authenticity in the API’s context. Both private as well as public APIs can utilize this kind of verification.

Authorization

The API approval procedure verifies the individual's credentials and grants permission to use the app's features. It's a standard procedure in online applications, which can be carried out by requesting HTTP that includes the proper header and token. After that, the API will respond with details on the extent to which the request was valid.

Fuzz testing 

The fuzzing approach aims to destroy the network or find bugs in security by sending arbitrary or erroneous information to an API. An intruder could gain unauthorized access to confidential information or take over the API by disrupting the network.

An API can be attacked from both ends of the connection via fuzzing. In order to bring down the system or gain possession of confidential information, server-side fuzzing involves transmitting illicit data towards servers through the API.

What vulnerabilities can API testing protect against?

API security evaluations can cover numerous threats connected to APIs. The top 3 API flaws have been generated by OWASP, and this list serves as an invaluable resource for what API security assessments should focus on first:

• API1 Broken Object Level Authorization
• API2 Broken User Authentication 
• API3 Excessive Data Exposure 
• API4 Lack of Resources & Rate Limiting
• API5 Broken Function Level Authorization
• API6 Mass Assignment
• API7 Security Misconfiguration
• API8 Injection
• API9 Improper Assets Management
• API10 Insufficient Logging & Monitoring

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API Security Testing Checklist

For testing regarding security, certain information has already been covered. Let's organize it into a checklist you may use to plan and carry out your evaluation approach: 

• Build an independent testing setup that has the potential to evaluate your APIs without disrupting business. Initially, create functional assessments for the blissful path and then execute them using an arsenal of your choosing.
• Employing identical tools creates adverse evaluations for extreme scenarios that can cause issues associated with security-test verification first for a fast win. So, have a way to distinguish between your deployments.
• ‍Make comprehensive documentation for all your APIs' roles and other authentication methods. Make tests on individuals with a variety of rights and access to secret assets. Next, create test scenarios where these individuals try to get forbidden resources.
• Don't consider your API a mystery. Work consistently to recognize backend loopholes (for example, mass assignments, SQL injections, etc.).
• ‍Make evaluations with data that exceeds the restrictions. Instances include adding more attributes, exceeding set limitations, and (if required) commands of SQL injections.
• ‍Keep an eye out for any internal information leaks in all error answers.

Incorporate safety evaluations into performance assessments to guarantee that any strange behavior under stress does not compromise privacy.