Vincent’s Blog

Be cool, I am not encoraging no one to start a life in the dark side of IT. Many times admins or users have a server or a computer that has accounts and need to know their passwords. For example: a ftp server with a lot of created accounts that people from other companies use. It is not an option call to call to 300 or 1000 users telling that their passwords changed when you need to upgrade server’s hardware or operating system.

Until some time ago I used, when I needed, a shareware software called L0phCrack, that was discontinued on 2006. Beside the shareware problem, after some time it stops to work, LOphCrack crack passwords using brute force method. It takes hours to crack them.

I needed some days ago again and tried to find another software in the internet and I found Ophcrack. It is a Open Source, free and crack passwords using a dictionary of hashes. It is much faster than L0phCrack, almost 8 times in my case.

To crack passwords you will need to have access to SAM and SECURITY files of the target machine. There are stored accounts and hashes of passwords. The install files of Ophcrack are not big, but the tables are huge, starting from 360 MB up to 8 GB. Smaller tables can be used to crack simple passwords that uses letters and numbers. Bigger ones are used to crack complex passwords. It Can looks a lot to download but belive me, if you need to crack complex passwords using brute force method will take much longer than the download time…

Wanna test? Click on ophcrack.sourceforge.net. There is also a bootable version that allows you to access SAM and SECURITY files with out any program install on target computer.

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