Set enforce complex password Ubunut 22.04

1) Install the libpam-pwquality package

sudo apt update

sudo apt install libpam-pwquality

2) Edit the PAM password configuration file  open the /etc/pam.d/common-password file for editing:

sudo nano /etc/pam.d/common-password

3) Add or modify the pwquality settings:

password requisite pam_pwquality.so retry=3

password requisite pam_pwquality.so retry=3 minlen=12 dcredit=-1 ucredit=-1 lcredit=-1 ocredit=-1

retry=3: Allows 3 retries if the user enters an invalid password.

minlen=12: Requires a minimum password length of 12 characters.

dcredit=-1: Requires at least 1 digit.

ucredit=-1: Requires at least 1 uppercase letter.

lcredit=-1: Requires at least 1 lowercase letter.

ocredit=-1: Requires at least 1 special character (e.g., @, #, $).

4) Optional: Add additional password strength rules:

sudo nano /etc/security/pwquality.conf

Here you can add options like:

minlen = 12

dcredit = -1

ucredit = -1

lcredit = -1

ocredit = -1

maxrepeat = 2       # Prevent repeated characters

maxclassrepeat = 2  # Prevent excessive character class repetition

5) Save and exit: After editing

6) Test the configuration: 

sudo passwd <username>

Ref

• https://chatgpt.com/share/6708c50a-d480-8010-8ea4-418483178302