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Lock Accounts After Failed Password Attempts

An XCCDF Rule

Description

This rule configures the system to lock out accounts after a number of incorrect login attempts using pam_faillock.so. pam_faillock.so module requires multiple entries in pam files. These entries must be carefully defined to work as expected. Ensure that the file /etc/security/faillock.conf contains the following entry: deny = <count> Where count should be less than or equal to and greater than 0. In order to avoid errors when manually editing these files, it is recommended to use the appropriate tools, such as authselect or authconfig, depending on the OS version.

warning alert: Warning

If the system relies on authselect tool to manage PAM settings, the remediation will also use authselect tool. However, if any manual modification was made in PAM files, the authselect integrity check will fail and the remediation will be aborted in order to preserve intentional changes. In this case, an informative message will be shown in the remediation report. If the system supports the /etc/security/faillock.conf file, the pam_faillock parameters should be defined in faillock.conf file.

Rationale

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

ID
xccdf_org.ssgproject.content_rule_accounts_passwords_pam_faillock_deny
Severity
Medium
References
Updated



Remediation - Ansible

- name: Gather the package facts
  package_facts:
    manager: auto
  tags:
  - CJIS-5.5.3
  - DISA-STIG-OL07-00-010320

Remediation - Shell Script

# Remediation is applicable only in certain platforms
if rpm --quiet -q pam; then

var_accounts_passwords_pam_faillock_deny='<xccdf-1.2:sub xmlns:xccdf-1.2="http://checklists.nist.gov/xccdf/1.2" idref="xccdf_org.ssgproject.content_value_var_accounts_passwords_pam_faillock_deny" use="legacy"/>'