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Cracking Bcrypt Hashes

linux-security-exploitation-password-cracking | Level: Easy  | Total Lab Runs: 0 | Premium Lab

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Lab Walkthrough Video:

Bcrypt is a popular 184-bit password hashing function designed by Niels Provos and David Mazières in 1999. It is based on blowfish cipher.  It is default password hashing algorithm for OpenBSD and other OSes like SUSE Linux. 

An Bcrypt hash entry for a password is provided in digest.txt file. The password is either taken from the dictionary or generated using the password policy. The digest.txt file and the dictionary file "1000000-password-seclists.txt" are present in the user's home directory.

Objective: Recover the password 

If the Dictionary attack fails then the password policy is:

  • Password length is less than 6 characters i.e. 0 < length < 4
  • Password can only contain characters from this character set:  a-z, 0-9

1. Password

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