Introduction
Web applications use parameters (or queries) to accept user input, take the following example into consideration
http://api.example.com/v1/userinfo?id=751634589
This URL seems to load user information for a specific user id, but what if there exists a parameter named admin which when set to True makes the endpoint provide more information about the user?
This is what Arjun does, it finds valid HTTP parameters with a huge default dictionary of 25,980 parameter names.
The best part? It takes less than 30 seconds to go through this huge list while making just 50-60 requests to the target.
Want to know how Arjun does that? Here's how.

Features

• Multi-threading
• Thorough detection
• Automatic rate limit handling
• A typical scan takes 30 seconds
• GET/POST/JSON methods supported
• Huge list of 25,980 parameter names

Note: Arjun doesn't work with python < 3.4

How to use Arjun?
A detailed usage guide is available on Usage section of the Wiki.\
An index of options is given below:

• Scanning a single URL
• Scanning multiple URLs
• Choosing number of threads
• Handling rate limits
• Delay between requests
• Including presistent data
• Saving output to a file
• Adding custom HTTP headers

Credits
The parameter names are taken from @SecLists.