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Old 03-06-2005, 05:34 AM   #1
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/etc/shadow crack

I have to find a way to crack a users "simple" password after I have gained access to the /etc/shadow file.

Now, i have tried using John the Ripper and it is taking years to figure the password out, maybe i am using it wrong but i copied the line in /etc/passwd to a file called passwd.txt and the hashed line in /etc/shadow to a file called shadow.txt.

I then run John the Ripper with: "unshadow passwd.txt shadow.txt", then i copy the output from that command to another file called temp.txt.

I then run John the Ripper again with the command: "john temp.txt"

It seems to be trying to crack it, but it is taking hours.

Does anyone know of a better hash cracker or what am doing wrong, I have to figure this out for a school project so any help would be greatly appreciated.

Old 03-06-2005, 06:09 AM   #2
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JTR is one of the best available. It is going to take awhile, as it does not actually "crack" a password, but insteads it encrypts various passwords using the same algorithm and compares that to the hash.
It basically startes at 0 and goes through all iterations to ZZZZZZZZZ including all upper- and lower-case letters and numbers.
"Decrypting" a UNIX password is impossible, thus this is the only approach.
Old 03-06-2005, 10:26 AM   #3
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The size and complexity of the password also makes a really big difference. Once you start getting over 8 characters, you'll be meauring cracking times in days/weeks rather than hours.
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Old 03-06-2005, 08:01 PM   #4
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Thanks for the input.

Greatly appreciate it.


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