Introduction:

During a routine assessment, a single JavaScript file was examined. What was found changed my approach forever. While complex tools were being run, a complete set of internal API routes was sitting in the public JavaScript bundle. This wasn’t a sophisticated attack — it was simply knowing where to look.

For many starting out, manually searching through JavaScript files feels like finding a needle in a haystack. The code is often minified, messy, and overwhelming.

In this beginner’s guide, a streamlined method is shared to find hidden API endpoints efficiently. What used to be tedious is now transformed into a simple, automated process.

What Exactly Are We Hunting For?

Think of an API endpoint as a dedicated phone line between two applications. For example, when your profile loads, the website might call https://api.example.com/v1/user/data.

These connections are often hidden within JavaScript files. Here’s what to watch for:

• Clear endpoint paths: api/v1/secure/adminList
• Full URLs…