cis-ubuntu2004-v300-2-1-18

DevOps & Security

Ensure web server services are not in use

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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_20.04_LTS_Benchmark_v3.0.0/cis-ubuntu2004-v300-2-1-18/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-ubuntu2004-v300-2-1-18/. Do not write files or run scripts until I approve.

After I approve, install the complete skill folder, including required referenced files, into that project location. Verify it is discoverable, then tell me its actual invocation name and how to use it. Do not claim it is installed until you have verified it.

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

2.1.18 Ensure web server services are not in use (Automated)

Profile

Level 1 - Server
Level 1 - Workstation

Description

Web servers provide the ability to host web site content. The two most common web server packages available are apache2 and nginx.

Rationale

If there is no need to run the system as a web server, it is recommended that the service be disabled to reduce the potential attack surface.

Audit Procedure

Command Line

Run the following commands to verify apache2 and nginx are not installed:

# dpkg-query -W -f='${binary:Package}\t${Status}\t${db:Status-Status}\n' apache2 nginx

If installed, run:

# systemctl is-enabled apache2.socket apache2.service nginx.service
# systemctl is-active apache2.socket apache2.service nginx.service

Verify the services are not enabled and not active.

Expected Result

apache2 and nginx should not be installed, or if installed, the services should be stopped and masked.

Remediation

Command Line

Run the following commands to stop, mask, and purge web servers:

# systemctl stop apache2.socket apache2.service nginx.service
# systemctl mask apache2.socket apache2.service nginx.service
# apt purge apache2 nginx

Default Value

apache2 and nginx are not installed by default.

References

NIST SP 800-53 Rev. 5: CM-7

CIS Controls

Controls Version	Control	IG 1	IG 2	IG 3
v8	4.8 Uninstall or Disable Unnecessary Services on Enterprise Assets and Software		x	x
v7	9.2 Ensure Only Approved Ports, Protocols and Services Are Running		x	x

MITRE ATT&CK Mappings: T1203, T1210, T1543, T1543.002 | TA0008 | M1042