Information
libpwquality provides common functions for password quality checking and scoring them based on their apparent randomness. The library also provides a function for generating random passwords with good pronounceability.
This module can be plugged into the password stack of a given service to provide some plug-in strength-checking for passwords. The code was originally based on pam_cracklib module and the module is backwards compatible with its options.
Strong passwords reduce the risk of systems being hacked through brute force methods.
Solution
Run the following command to install libpam-pwquality :
# apt install libpam-pwquality