Title

The system must require passwords to contain at least one special character. (Cat III impact)

Discussion

Requiring a minimum number of special characters makes password guessing attacks more difficult by ensuring a larger search space.

Check Content

To check how many special characters are required in a password, run the following command: $ grep pam_cracklib /etc/pam.d/system-auth /etc/pam.d/password-auth Note: The "ocredit" parameter (as a negative number) will indicate how many special characters are required. The DoD requires at least one special character in a password. This would appear as "ocredit=-1". If “ocredit” is not found or not set to the required value, this is a finding.

Fix Text

The pam_cracklib module's "ocredit=" parameter controls requirements for usage of special (or "other") characters in a password. When set to a negative number, any password will be required to contain that many special characters. When set to a positive number, pam_cracklib will grant +1 additional length credit for each special character. Edit /etc/pam.d/system-auth and /etc/pam.d/password-auth adding "ocredit=-1" after pam_cracklib.so to require use of a special character in passwords.

Additional Identifiers

Rule ID: SV-217894r603264_rule

Vulnerability ID: V-217894

Group Title: SRG-OS-000266

Expert Comments

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