# Cis Ubuntu1804 V220 2 2 12

> Ensure HTTP Proxy Server is not installed

- Skill: `cyberstrikeus/cis-ubuntu1804-v220-2-2-12` (Agent Skill)
- Install (CLI): `npx skillmds@latest add cyberstrikeus/cis-ubuntu1804-v220-2-2-12`
- Raw SKILL.md: https://api.skillmd.com/api/skills/cyberstrikeus/cis-ubuntu1804-v220-2-2-12/raw
- Safety review: PASS (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: cyberstrikeus (https://skillmd.com/u/cyberstrikeus)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/cyberstrikeus/cis-ubuntu1804-v220-2-2-12

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# 2.2.12 Ensure HTTP Proxy Server is not installed (Automated)

## Profile

- Level 1 - Server
- Level 1 - Workstation

## Description

Squid is a standard proxy server used in many distributions and environments.

## Rationale

If there is no need for a proxy server, it is recommended that the squid proxy be deleted to reduce the potential attack surface.

## Audit Procedure

### Command Line

Run the following command to verify `squid` is not installed:

```bash
# dpkg-query -s squid &>/dev/null && echo "squid is installed"
```

Nothing should be returned.

## Expected Result

No output (empty result).

## Remediation

### Command Line

Run the following command to remove `squid`:

```bash
# apt purge squid
```

## References

1. NIST SP 800-53 Rev. 5: CM-6, CM-7

Additional Information:

Several HTTP proxy servers exist. These and other services should be checked.

## 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