To execute John, change to the correct directory by typing:
cd ../run
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After placing a hashed file into this directory, type:
john ??“i pwdump
The passwords will be broken and displayed on the screen.
344 Practical Hacking Techniques and Countermeasures
To interrupt the ???cracking??? process hold down the Ctrl key and press the
C key.
John keeps track of the passwords it finds for each hashed file. To verify
what passwords were found, type:
john ??“show pwdump
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The passwords will be displayed unencrypted in the hash file with information
separated by a colon (:). The biggest ones of concern are the first three:
Username
Password
User ID
*Note: User ID is important because a user account can be renamed. In this example
this is a hashed file from a Windows target. Referring to Chapter 3, each user
is assigned a static user ID. The Administrator account on a Windows machine
will always be 500.
John the Ripper allows for the cracking of Linux/Unix password files as
well. The only limitation is if the password is ???shadowed??? with an asterisk (*).
346 Practical Hacking Techniques and Countermeasures
Lab 58: Brute-Force FTP Password
Brute-Force an FTP Password Connection: BruteFTP
Prerequisites: None
Countermeasures: Secured FTP, known as Secured Shell Client (SSL) or
Secure FTP Client (SFTP)
Description: File Transfer Protocol (FTP) is used to transfer files between
computers and is still widely in use.
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