Your Ultimate Guide to API Fuzzing

What is API Fuzzing?

What is API Fuzzing?

API fuzzing is a type of API testing that uses a fuzzing engine or API fuzzer to generate various test inputs and possible request sequences to the fuzz target, or in this case, a web API via API calls. The API fuzzer takes note of the API response and documents if a test input uncovers a bug or possible security vulnerability.

Why API Fuzzing Is Important

Web APIs are everywhere! We interact with APIs every day. We use APIs to write a tweet, discover music, make a purchase, or anything else you can imagine. We write applications that are composed with other APIs using patterns such as API Gateways.

It is empowering to interact with a well-designed and documented API to build the right solutions for yourself and your customers.

A well-behaved API will use HTTP response status codes to let you know if you are doing something right (200-209) or wrong (400-499).

API Fuzz Testing then is important to ensure your APIs are behaving properly and prevent a rogue request type from leaving you open to security concerns.

API Fuzzing with Postman

API Fuzzing with Postman

Postman Collections are a great way to document, test, and share your APIs . With Mayhem for API, a fuzzing tool, you can squeeze even more testing out of your existing postman collections, without having to write an additional test case! Mayhem for API generates all sorts of values for those parameters using a custom fuzzing engine without any assistance or test inputs from you.

API Fuzzing with GitHub

API Fuzzing with GitHub

One of Mayhem for API's guiding principles is to seamlessly integrate into existing developer ecosystems. We integrated Mayhem for API with GitHub from Day 1. For instance, you can sign up to our service with your GitHub account. Our GitHub App enables Mayhem for API to add GitHub Checks directly in your Pull Request.

API Fuzzing with OpenAPI Specs

As organizations adopt Digital Transformation strategies to deliver faster value to customers, there has been an exponential reliance on microservices. The fundamental role microservices play in optimizing a business’ operations have led to greater diligence on validating API performance and reliability.

API Fuzzing Your Own Projects

See what Mayhem produces in the hands of someone who knows the target API or REST API in and out. Because fuzzing is random, having Mayhem in the CI pipeline means occasionally having a build fail when it hits an unrelated error; this will stop being an issue in time.

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