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Old 12-05-2010, 08:53 AM   #1
prasanna.R
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Encryption question


how to decrypt the passwd in /etc/shawdow
 
Old 12-05-2010, 10:05 AM   #2
MTK358
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Quote:
Originally Posted by prasanna.R View Post
how to decrypt the passwd in /etc/shawdow
This thread is no place to ask questions.

Also, how do I know that you're not decrypting passwords for malicious purposes?
 
Old 12-06-2010, 01:55 AM   #3
prasanna.R
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Quote:
Originally Posted by MTK358 View Post
This thread is no place to ask questions.

Also, how do I know that you're not decrypting passwords for malicious purposes?
Actually, i was trying to learn how to decrypt it?..and i ll be using that only for my own personal purpose only senior
i wont use it for wrong purpose senior...
 
Old 12-06-2010, 02:13 AM   #4
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You can't. The values in shadow are hashes, not encrypted passwords.
There's no "reverse" for it, only brute force cracking attempts.



Cheers,
Tink
 
Old 12-06-2010, 08:57 AM   #5
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http://en.wikipedia.org/wiki/Cryptographic_hash
 
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Old 12-07-2010, 02:24 AM   #6
prasanna.R
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Quote:
Originally Posted by Tinkster View Post
You can't. The values in shadow are hashes, not encrypted passwords.
There's no "reverse" for it, only brute force cracking attempts.



Cheers,
Tink
what is brute force cracking attempts senior?
is there any other way ? senior.....
 
Old 12-07-2010, 02:33 AM   #7
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Install john ripper(www.nmap.org) in your machine and copy the shadow file to the crack container. Start the cracker and you will receive the password with in some minutes/hours (depend on the password critical combination). John ripper is one of the famous tool for password decrypting.

Note: you should not misuse the tool.

Best Regards,
 
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Old 12-07-2010, 02:35 AM   #8
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Brute force is like an engine that will try all the possible combinations of passwords till it gets the right one.
But if the password has been encrypted by something like sha512 or des it will take perhaps a million years of computing power to break one password. Not recommended. If you are the sysadmin then you have some tools at your disposal that would send user an email if their password is weak but then it will not tell _you_ the password.
Hope this helps.
 
Old 12-07-2010, 06:35 AM   #9
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SilverBlack

I believe Brute force engine will try login to the account and guess the password with the stored dictionary word. :P

Dear prasanna.R,

to decrypt the password go this site and find the tool johnripper password cracker. Install it in your machine or in a separate machine and copy the /etc/shadow file to the container. Read the manual page and start running the tool. You will get your password decrypted.

Regards,
 
Old 12-07-2010, 09:03 AM   #10
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Thanks for correcting that one . I was not thinking clearly.
 
Old 12-07-2010, 11:22 AM   #11
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Quote:
Originally Posted by prodev05 View Post
SilverBlack

I believe Brute force engine will try login to the account and guess the password with the stored dictionary word. :P

Dear prasanna.R,

to decrypt the password go this site and find the tool johnripper password cracker. Install it in your machine or in a separate machine and copy the /etc/shadow file to the container. Read the manual page and start running the tool. You will get your password decrypted.

Regards,

And again, just to avoid language confusion with visitors:

John the ripper will NOT decrypt your password. It will try
large numbers of hashes, and see whether any match your hash.
If one does, the password John was trying happens to be the
one that is in your shadow file.

This is NOT "decrypting a password".



Cheers,
Tink
 
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Old 12-09-2010, 03:50 AM   #12
prodev05
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Yes its not a password decrypting tool. Its a password cracker.

Dear Visitors,

John Ripper is not a password decrypting tool. Its a famous password cracking tool.

_____________________

Tinkster

Thanks for correcting.

Regards
 
Old 12-09-2010, 09:02 AM   #13
prasanna.R
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ya i got it senior......and i installed it too....but i couldn't know how to use ......any way i ll it try myself senior..
thanks you very much senior....

Last edited by prasanna.R; 12-09-2010 at 09:05 AM.
 
  


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