# Cis Ubuntu1204 V110 7 3 3

> Disable IPv6

- Skill: `cyberstrikeus/cis-ubuntu1204-v110-7-3-3` (Agent Skill)
- Install (CLI): `npx skillmds@latest add cyberstrikeus/cis-ubuntu1204-v110-7-3-3`
- Raw SKILL.md: https://api.skillmd.com/api/skills/cyberstrikeus/cis-ubuntu1204-v110-7-3-3/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-ubuntu1204-v110-7-3-3

---


# 7.3.3 Disable IPv6 (Not Scored)

## Profile Applicability

- Level 1

## Description

Although IPv6 has many advantages over IPv4, few organizations have implemented IPv6.

## Rationale

If IPv6 is not to be used, it is recommended that it be disabled to reduce the attack surface of the system.

## Audit Procedure

### Using Command Line

Run the following command to determine if IPv6 is enabled:

```bash
ip addr | grep inet6
```

## Expected Result

No results should be returned.

## Remediation

### Using Command Line

Create or edit the file `/etc/sysctl.conf` and add the following lines:

```bash
net.ipv6.conf.all.disable_ipv6=1
net.ipv6.conf.default.disable_ipv6=1
net.ipv6.conf.lo.disable_ipv6=1
```

Run the following command or reboot to apply the changes:

```bash
sysctl -p
```

## Default Value

IPv6 is enabled by default.

## References

- CIS Ubuntu 12.04 LTS Server Benchmark v1.1.0

## Profile

Level 1 - Not Scored