Information
The pwquality maxsequence option sets the maximum length of monotonic character sequences in the new password. Examples of such sequence are 12345 or fedcb . The check is disabled if the value is 0.
Note: Most such passwords will not pass the simplicity check unless the sequence is only a minor part of the password.
Use of a complex password helps to increase the time and resources required to compromise the password. Password complexity, or strength, is a measure of the effectiveness of a password in resisting attempts at guessing and brute-force attacks.
Password complexity is one factor of several that determines how long it takes to crack a password. The more complex the password, the greater the number of possible combinations that need to be tested before the password is compromised.
Solution
Create or modify a file ending in .conf in the /etc/security/pwquality.conf.d/ directory or the file /etc/security/pwquality.conf and add or modify the following line to set maxsequence to 3 or less and not 0 . Ensure setting conforms to local site policy:
Example:
# sed -ri 's/^\s*maxsequence\s*=/# &/' /etc/security/pwquality.conf
# printf '\n%s' "maxsequence = 3" >> /etc/security/pwquality.conf.d/50-pwmaxsequence.conf
- OR/IF - the pam-config tool has been used to configure the global PAM configuration files.
Run the following command to set maxsequence to 3 or less and not 0 . Ensure setting conforms to local site policy:
Example:
# pam-config -a --cracklib-maxsequence=3