The system must require passwords to contain no more than three consecutive repeating characters.

From Red Hat Enterprise Linux 6 Security Technical Implementation Guide

Associated with: CCI-000366

SV-50494r2_rule The system must require passwords to contain no more than three consecutive repeating characters.

Vulnerability discussion

Passwords with excessive repeating characters may be more vulnerable to password-guessing attacks.

Check content

To check the maximum value for consecutive repeating characters, run the following command: $ grep pam_cracklib /etc/pam.d/system-auth Look for the value of the "maxrepeat" parameter. The DoD requirement is 3. If maxrepeat is not found or not set to the required value, this is a finding.

Fix text

The pam_cracklib module's "maxrepeat" parameter controls requirements for consecutive repeating characters. When set to a positive number, it will reject passwords which contain more than that number of consecutive characters. Add "maxrepeat=3" after pam_cracklib.so to prevent a run of (3 + 1) or more identical characters. password required pam_cracklib.so maxrepeat=3

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