Keyboard Dictionaries
By far the most popular download from my dictionary based rainbow tables has been the input dictionary I created based on keyboard combos. It's been downloaded close to 2000 times which means about 1995 more people have downloaded it than read this blog ;) So of course I'm looking to improve on it. The original dictionary was created thanks to an abundance of free time and my own personal lack of carpal tunnel syndrom as I typed each entry into it. The problem of course was that I've since found out that there were many keyboard combos that I missed.
So that's why God, (or at least Solar Designer), created external moduals for John the Ripper. One of them simulates a keyboard layout so if you type
./john -stdout -external=keyboard
It will start to output different strings based on how close the keys are on your actual keyboard. Me being the lazy person I am of course decided to pipe the output of that into a file to create a new and improved "keyboard dictionary". The problem is I left it running and after a while started to wonder why it hadn't stopped. Checking on it, I found that the file it had been creating filled up over 18 gigs of disk space. That's not acceptable.
I really don't have anything else to offer right now, but I just wanted to give you a status update and let you know it's a problem I'm working on ;)
So that's why God, (or at least Solar Designer), created external moduals for John the Ripper. One of them simulates a keyboard layout so if you type
./john -stdout -external=keyboard
It will start to output different strings based on how close the keys are on your actual keyboard. Me being the lazy person I am of course decided to pipe the output of that into a file to create a new and improved "keyboard dictionary". The problem is I left it running and after a while started to wonder why it hadn't stopped. Checking on it, I found that the file it had been creating filled up over 18 gigs of disk space. That's not acceptable.
I really don't have anything else to offer right now, but I just wanted to give you a status update and let you know it's a problem I'm working on ;)
Comments
With the keyboard rainbow tables I previously made, the actual input dictionary was very small, (~650 words), but I combined the words together since that's how I've found most people create their passwords, (if they are using a keyboard layout). Aka "1qaz&UJMqwerty". This way even though the input dictionary was small, the number of guesses was fairly substantial
Combination of three keyboard combos:274 million guesses
Combination of four keyboard combos:178 billion guesses
Thus it pays to have a smaller input dictionary for those types of attacks. What I'm trying to do though is build a much bigger input dictionary for cracking passwords where people append/prepend a keyboard combo to a regular word, such as "1qaz@WSXpassword". Also it seems like people who use uncommon keyboard combos tend not to chain them as much, aka they tend to use only one or two of them, not four or five.
1) only takes into account lowercase lettering. Fix: output results into a .dic file - then use with --rules:nt (use the new rules:nt post on john-users mailing list). It misses even easy stuff like qweQWE.
2) It misses very obvious patterns: Like qweqaz (look at your keyboard) or qweewq
3) no special characters. Passwords like 123!@# are super-obvious: Fix: Make a rule that converts all numbers to special character equivalents (1 = ! 2=@ etc). Ive posted a rule that does this on john-users (I think I did..).
Pretty much I dont use --external:keyboard anymore because I've made my own dictionary files - that (when combined with different --rules) are much more powerful.
-Minga
Google a pdf called "Visualizing Keyboard Pattern Passwords":
http://cs.wheatoncollege.edu/~mgousie/comp401/amos.pdf
This must be implemented somewhere but I have not found it.