cis-gcp-cos-5-3-1-4

name	cis-gcp-cos-5.3.1.4
description	Ensure inactive password lock is 30 days or less
category	cis-gcp-cos
version	1.2.0
author	cyberstrike-official
tags	["cis","gcp","container-optimized-os","shadow","password-expiration","user-accounts"]
cis_id	5.3.1.4
cis_benchmark	CIS Google Container-Optimized OS Benchmark v1.2.0
tech_stack	["gcp","linux"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

5.3.1.4 Ensure inactive password lock is 30 days or less (Automated)

Description

User accounts that have been inactive for over a given period of time can be automatically disabled. It is recommended that accounts that are inactive for 30 days after password expiration be disabled.

Rationale

Inactive accounts pose a threat to system security since the users are not logging in to notice failed login attempts or other anomalies.

Audit Procedure

Run the following command and verify INACTIVE conforms to site policy (no more than 30 days):

# useradd -D | grep INACTIVE

INACTIVE=30

Verify all users with a password have Password inactive no more than 30 days after password expires:

Run the following command and Review list of users and INACTIVE to verify that all users' INACTIVE conforms to site policy (no more than 30 days):

# grep -E '^[^:]+:[^\!*]' /etc/shadow | cut -d: -f1,7

<user>:<INACTIVE>

Expected Result

INACTIVE should be 30 or less from useradd -D and for all users with a password in /etc/shadow.

Remediation

Run the following command to set the default password inactivity period to 30 days:

# useradd -D -f 30

Modify user parameters for all users with a password set to match:

# chage --inactive 30 <user>

Additional Information:

You can also check this setting in /etc/shadow directly. The 7th field should be 30 or less for all users with a password.

Note: A value of -1 would disable this setting.

CIS Controls

Controls Version	Control	IG 1	IG 2	IG 3
v8	5.2 Use Unique Passwords - Use unique passwords for all enterprise assets. Best practice implementation includes, at a minimum, an 8-character password for accounts using MFA and a 14-character password for accounts not using MFA.	x	x	x
v7	4.4 Use Unique Passwords - Where multi-factor authentication is not supported (such as local administrator, root, or service accounts), accounts will use passwords that are unique to that system.