From kitploit.com
For the longest of times, content discovery has been focused on finding files and folders. While this approach is effective for legacy web servers that host static files or respond with 3xx’s upon a partial path, it is no longer effective for modern web applications, specifically APIs.
Over time, we have seen a lot of time invested in making content discovery tools faster so that larger wordlists can be used, however the art of content discovery has not been innovated upon.
Kiterunner is a tool that is capable of not only performing traditional content discovery at lightning fast speeds, but also bruteforcing routes/endpoints in modern applications.
Modern application frameworks such as Flask, Rails, Express, Django and others follow the paradigm of explicitly defining routes which expect certain HTTP methods, headers, parameters and values.