When testing web applications, discovering what functionality is available is key to finding vulnerabilities. Ideally you want to find as many application pages as possible. You can do this by using web‑crawling or spidering tools to uncover indexed pages, as well as employing forced‑browsing techniques. When doing forced browsing you are looking for pages that are not indexed on the site but still available. Forced-browsing is more useful when the applications user interface (UI) is limited, but even on applications with a large UI, forced-browsing can return webpages that would otherwise not be known.

Recently, I got this question:

"I found a URL that is returning a default homepage, but it has no links or navigation. How do I find out if the application has functionality?”
So, I figured I would write up a quick guide on how I find content in modern web applications.