Title

Amazon Linux 2023 must automatically lock an account until the locked account is released by an administrator when three unsuccessful logon attempts in 15 minutes occur. (Cat II impact)

Discussion

By limiting the number of failed logon attempts, the risk of unauthorized system access via user password guessing, otherwise known as brute-forcing, is reduced. Limits are imposed by locking the account.

Check Content

Note: If the system administrator demonstrates the use of an approved centralized account management method that locks an account after three unsuccessful logon attempts within a period of 15 minutes, this requirement is not applicable. Verify Amazon Linux 2023 locks an account after three unsuccessful logon attempts within a period of 15 minutes with the following command: $ grep fail_interval /etc/security/faillock.conf fail_interval = 900 If the "fail_interval" option is not set to "900" or less (but not "0"), the line is commented out, or the line is missing, this is a finding.

Fix Text

Configure Amazon Linux 2023 to automatically lock an account after three unsuccessful logon attempts in 15-minutes. First, ensure that the system is configured with authselect, i.e., using sssd profiles: $ sudo authselect select sssd [--force] Then, enable the faillock feature: $ sudo authselect enable-feature with-faillock Then edit the "/etc/security/faillock.conf" file as follows: fail_interval = 900

Additional Identifiers

Rule ID: SV-274156r1120456_rule

Vulnerability ID: V-274156

Group Title: SRG-OS-000329-GPOS-00128

Expert Comments

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