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Old 02-23-2009, 01:37 AM   #1
abrenar
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Decrypt Password in linux


any software for Ubuntu that can decrypt linux password found in /etc/shadow ?
 
Old 02-23-2009, 01:44 AM   #2
shahz
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check out john the ripper I think thats good one.
 
Old 02-23-2009, 01:49 AM   #3
abrenar
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tnx Shahz. how can i install it to my ubuntu intrepid box?
 
Old 02-23-2009, 01:56 AM   #4
shahz
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try googling how to use john the ripper you would come to know.
 
Old 02-23-2009, 02:53 AM   #5
jschiwal
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John the Ripper can decrypt a week password and be used to test for week dictionary passwords. Brute forcing a strong password hash for Linux would probably take way too long to be worthwhile. It would be easier to change the password as root, if you forgot your password.
 
Old 02-23-2009, 04:42 AM   #6
Lee_Ball
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John the ripper gets better with use too, so it might be worth running it from a penstick. Its a simple download that you then run from the command line. I usually copy out the /etc/shadow file to where I'm running John the ripper from.
 
Old 03-03-2009, 01:21 AM   #7
abrenar
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i already got what i need.



apt-get install crack


man crack.
for you to know what it is.

peace \m/
 
Old 03-03-2009, 12:14 PM   #8
anomie
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Not to split hairs, but you're not decrypting a password. It was hashed. You're brute forcing the hashed password, not reversing the hash.
 
Old 03-03-2009, 02:59 PM   #9
T74marcell
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Just a few searched hints for the curious minded:

Different types of hashings can be in play:
Quote:
"To modify the contents of the shadow file, users generally invoke the passwd program, which in turn is largely depending on PAM. For example, the type of hash used is dictated by the configuration of the pam_unix.so module. By default the MD5 hash is used, while the newer pam_unix2.so module is also capable of stronger hashes such as blowfish."
See: http://en.wikipedia.org/wiki/Shadow_password

Quote:
"vipw is a small computer program which enables a Unix system administrator to comfortably edit the "passwd" and "Shadow password" files. It comes bundled in the "Shadow" software package."
See: http://www.linuxmanpages.com/man8/vipw.8.php

Authenticate A User (or a PHP cript) Using Same Password As Linux Password:
http://www.bigresource.com/PHP-Authe...-1CLOOrvX.html

----------
T74marcell

Arch Linux

Last edited by T74marcell; 03-14-2009 at 01:42 AM.
 
  


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