cis-ubuntu1604-v200-1-8-1

DevOps & Security

Ensure GNOME Display Manager is removed

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How to use this skill

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Prompt to paste

I want to install this Agent Skill for this project in Codex.

Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/CIS_benchmarks/Operating_Systems/Ubuntu/CIS_Ubuntu_Linux_16.04_LTS_Benchmark_v2.0.0/cis-ubuntu1604-v200-1-8-1/SKILL.md

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First, summarize what it does, its dependencies, license status if identifiable, and any risks. Show the exact files you propose to add under .agents/skills/cis-ubuntu1604-v200-1-8-1/. Do not write files or run scripts until I approve.

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Copying this prompt does not install or run the skill. Review third-party files before use. Codex skill guide

CIS Ubuntu Linux 16.04 LTS Benchmark v2.0.0 - 1.8.1

Profile Applicability

Level 2 - Server

Description

The GNOME Display Manager (GDM) is a program that manages graphical display servers and handles graphical user logins.

Rationale

If a Graphical User Interface (GUI) is not required, it should be removed to reduce the attack surface of the system.

Impact

Removing the GNOME Display manager will remove the Graphical User Interface (GUI) from the system.

Audit Procedure

Command Line

Run the following command and verify gdm3 is not installed:

dpkg -s gdm3 | grep -E '(Status:|not installed)'

Expected output: dpkg-query: package 'gdm3' is not installed and no information is available

Expected Result

The gdm3 package should not be installed on server systems.

Remediation

Command Line

Run the following command to uninstall gdm3:

apt purge gdm3

Default Value

Not applicable.

References

None.

CIS Controls

Controls Version	Control
v7	2.6 Address unapproved software

Assessment Status

Manual