RHEL 9 must automatically lock an account when three unsuccessful logon attempts occur during a 15-minute time period.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-258056	RHEL-09-411085	SV-258056r958736_rule		Medium

Description
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. Satisfies: SRG-OS-000329-GPOS-00128, SRG-OS-000021-GPOS-00005

STIG	Date
Red Hat Enterprise Linux 9 Security Technical Implementation Guide	2024-06-04

Details

Check Text ( C-61797r926153_chk )
Verify RHEL 9 locks an account after three unsuccessful logon attempts within a period of 15 minutes with the following command: 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. $ 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.

Check Text ( C-61797r926153_chk )

Verify RHEL 9 locks an account after three unsuccessful logon attempts within a period of 15 minutes with the following command:

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.

$ 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 (F-61721r926154_fix)
To configure RHEL 9 to lock out the "root" account after a number of incorrect login attempts within 15 minutes using "pam_faillock.so", enable the feature using the following command: $ authselect enable-feature with-faillock Then edit the "/etc/security/faillock.conf" file as follows: fail_interval = 900