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cis-ubuntu1804-v220-2-2-6

DevOps & Security
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Ensure NFS is not installed

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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_18.04_LTS_Benchmark_v2.2.0/cis-ubuntu1804-v220-2-2-6/SKILL.md

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

2.2.6 Ensure NFS is not installed (Automated)

Profile

  • Level 1 - Server
  • Level 1 - Workstation

Description

The Network File System (NFS) is one of the first and most widely distributed file systems in the UNIX environment. It provides the ability for systems to mount file systems of other servers through the network.

Rationale

If the system does not export NFS shares, it is recommended that the nfs-kernel-server package be removed to reduce the remote attack surface.

Audit Procedure

Command Line

Run the following command to verify nfs is not installed:

# dpkg-query -s nfs-kernel-server &>/dev/null && echo "nfs-kernel-server is installed"

Nothing should be returned.

Expected Result

No output (empty result).

Remediation

Command Line

Run the following command to remove nfs:

# apt purge nfs-kernel-server

References

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

CIS Controls

  • v8: 4.8 - Uninstall or Disable Unnecessary Services on Enterprise Assets and Software
  • v7: 9.2 - Ensure Only Approved Ports, Protocols and Services Are Running