cis-ubuntu1804-v220-4-3-5

name	cis-ubuntu1804-v220-4-3-5
description	Ensure re-authentication for privilege escalation is not disabled globally
category	cis-iam
version	2.2.0
author	cyberstrike-official
tags	["cis","ubuntu","linux","ubuntu-18.04","sudo","privilege-escalation"]
cis_id	4.3.5
cis_benchmark	CIS Ubuntu Linux 18.04 LTS Benchmark v2.2.0
tech_stack	["ubuntu","linux"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

CIS Ubuntu Linux 18.04 LTS Benchmark v2.2.0 - Control 4.3.5

Profile Applicability

• Level 1 - Server
• Level 1 - Workstation

Description

The operating system must be configured so that the !authenticate option is not used in /etc/sudoers or in any included sudoers file.

Rationale

Without re-authentication, users may access resources or perform tasks for which they do not have authorization. When operating systems provide the capability to escalate a functional capability, it is critical the user re-authenticate.

Audit Procedure

Command Line

Run the following command to verify that !authenticate is not configured:

grep -r "!authenticate" /etc/sudoers /etc/sudoers.d/

Expected Result

Nothing should be returned. If output is returned, it means re-authentication has been disabled.

Remediation

Command Line

Remove any occurrences of !authenticate found in /etc/sudoers or files in /etc/sudoers.d/.

Use visudo to edit the files:

visudo
visudo -f /etc/sudoers.d/<filename>

References

1. NIST SP 800-53 Rev. 5: IA-11

CIS Controls

v8 - 5.4 Restrict Administrator Privileges to Dedicated Administrator Accounts.

v7 - 4.3 Ensure the Use of Dedicated Administrative Accounts.

Profile Applicability

• Level 1 - Server
• Level 1 - Workstation

Assessment Status

Automated