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Message-ID: <CAHM5tkOJxBGHe6nuGVdsDHCYLczDNjCgdaMTJygQ_dP1JoKyBQ@mail.gmail.com> Date: Wed, 3 Jul 2013 14:00:56 -0300 From: José Luis Herrera <jl200520@...il.com> To: john-users@...ts.openwall.com Subject: exoof's write-up for hashrunner 2013 First of all I apologize for my late write-up, I've just had some health problems but now am good to go. I didn't have any kind of experience before regarding a cracking passwords contest. But I got over it and could help a bit. Decided to participate due to my interestests on cryptography, also I've suscribed to the john-users list more or less 1 year and few months ago, also saw the last year contestbut thought well am not well prepared nor do know how to use john properly, but this time I started using it properly either reading the documentation/wiki as well as blogs, older write-ups, etc. Then proceeded to contact Aleksey and Solar to test my luck, and thanks to them I got my first experience in the whole process that smart password cracking process involves. Preparation: I've used to collect some wordlists either from leaks or from somewhere that could provide a good wordlist to start working with, so I've got them long before the contest but didn't provide any huge improvement at all. When I got accepted to participate in the contest, just prepared my machines to install john and start testing some attacks against hashes from the last year hash-runner contest as a suggestion from Aleksey. Software: JtR Hardware: - 2500k, q6600 and i5 760 at stock clocks Time spent: 30 or 35 hours more or less Attacks: Before anything just checked every contest file and decided with which type of hash I would feel better working. Then I saw md5's file and thought well it would be good to start with, thanks to a script from dhiru IIRC we could crack effectively the broken-md5 hashes, after a few hours when I got up saw some hits and some patterns related with the cosmos, so got on the irc and other members just said there are more patterns but most of them related to the space with some mangling rules. I've left md5 with an incremental attack while I started working on bcrypt where i've just got only one hit during the whole contest. When md5 started to get stuck decided to work with some rules such as After that, asked on the irc which hash needed some help and got told try some luck with keccak-256 where I also got some hits after a few hours and started to work on rules such as korelogic ones to try to buff this hash type a bit more. When there were a few hours and didn't get any md5 hit, just stopped the work on it and tried my work on md4 where things were good after aplying some rules and comparing results with the team, then the team said we got some colours+l33t over here and things started to go smoothly. After that started to look into sha-512 where i've got very few hits, a bit dissapointing but things must go on and tried luck with pix where I've left a machine running incremental mode for 6 hours and got nothing, Personal opinion: Since it was my first contest I thought that the contest itself was good planned, and the art of password cracking is a matter of time, interest and continuously improvements, just realized that you can't go blind on cracking every hash without even looking at what did you found neither just thinking that low hits means you did bad, instead it will help to analyze what in this case the host of hash-runner thought/used to make those hashes. A big problem with my participation on the contest was that when the conteststarted it was 2 am over here and things got a bit complicated, also the fact that it got during work-days, hopefully next year it'll be on a weekend. On the 2nd day of the contest one my machines failed and got one rig out of the game, but after talking with other team members on the irc, having too many machines for this kind of contests doesn't benefits you if you can't use them properly, after that i've used mainly the 2500k machine and left the q6600 for just some long and slow work. This way I've felt way more productive and could focus on what really was necessary. I guess that someday when I get more experience I could use more machines and produce improvements instead of just destroying progress, also I hope that the next time I can help a bit more the team. I didn't think that my contributions were great but OK. And that thinking is the most important part of the contest. Summary: I'd like to thank the organizers for making this type of contests and the team itself due to the awesome people that are on it and also the ones that didn't were on the irc during contest time but offered tips, help, etc via ml. And also would like to thank Aleksey and Solar for allowing me to join the team, knowing that I've got no-experience in contests. -- ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ Regards, Jose L. Herrera
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