JohnTheRuler

Overview:

This is a quick blog post to discuss a tool I’ve been developing over the past week or so. During a couple recent CTF competitions I found myself needing a quick and easy method of testing custom John The Ripper wordlist rules. I decided to recreate most of the important John rules and compiled it all into a javascript application that is hosted on my GitHub pages.

Uses and Demos:

I see a couple of valid use cases for this tool.

1. Testing rules to ensure John is covering the edge cases you want it to cover
2. Generating wordlists from a relatively small number of starting words
3. An all in one space to remember and learn John’s wordlist rules

I use John’s custom rules here and there throughout the year. I never use it enough to commit all of the interesting switches to memory so I plan on using this as my one stop shop for getting reintroduced and testing all of these rules. This will save me a lot of time and googling and I hope it helps you as well :-)

Link:

https://www.davidjwolfe.com/JohnTheRuler
_{I know the name is dumb but it was the last think I thought about.}