API Abuse and Business Logic Testing

With this chapter, we will finish the fourth part of our book. We just learned about data exposure and information leakage, which are unfortunately very common nowadays. It is also unfortunate that there are even more dangerous ways to break API protection controls. Abusing the right way of using endpoints is one of them. Exploiting the API logic is another fearsome one.

API abuse refers to the misuse of an API beyond its intended purpose, leading to security vulnerabilities, data breaches, or service disruptions. Business logic testing involves identifying vulnerabilities in the application’s business rules and workflows. This ensures that the application behaves as intended in all scenarios. Together, these tests help secure APIs against misuse and logical flaws.

In this chapter, we will stay engaged with the advanced API topics, but we will learn why the business logic behind an API can impact the frequency and/or depth at which...