# Cis Ubuntu2004 V300 1 3 1 2

> Ensure AppArmor is enabled in the bootloader configuration

- Skill: `cyberstrikeus/cis-ubuntu2004-v300-1-3-1-2` (Agent Skill)
- Install (CLI): `npx skillmds@latest add cyberstrikeus/cis-ubuntu2004-v300-1-3-1-2`
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- 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-ubuntu2004-v300-1-3-1-2

---


# 1.3.1.2 Ensure AppArmor is enabled in the bootloader configuration (Automated)

## Profile

- Level 1 - Server
- Level 1 - Workstation

## Description

Configure AppArmor to be enabled at boot time and verify that it has not been overwritten by the bootloader boot parameters.

Note: This recommendation is designed around the grub bootloader, if LILO or another bootloader is in use in your environment enact equivalent settings.

## Rationale

AppArmor must be enabled at boot time in your bootloader configuration to ensure that the controls it provides are not overridden.

## Audit Procedure

### Command Line

Run the following command to verify that all `linux` lines have the `apparmor=1` parameter set:

```bash
# grep "^\s*linux" /boot/grub/grub.cfg | grep -v "apparmor=1"
```

Nothing should be returned.

Run the following command to verify that all `linux` lines have the `security=apparmor` parameter set:

```bash
# grep "^\s*linux" /boot/grub/grub.cfg | grep -v "security=apparmor"
```

Nothing should be returned.

## Expected Result

No output should be returned for either command, indicating all linux lines have both `apparmor=1` and `security=apparmor` parameters set.

## Remediation

### Command Line

Edit `/etc/default/grub` and add the `apparmor=1` and `security=apparmor` parameters to the `GRUB_CMDLINE_LINUX=` line:

```
GRUB_CMDLINE_LINUX="apparmor=1 security=apparmor"
```

Run the following command to update the `grub2` configuration:

```bash
# update-grub
```

## References

1. NIST SP 800-53 Rev. 5: AC-3

## CIS Controls

| Controls Version | Control                                               | IG 1 | IG 2 | IG 3 |
| ---------------- | ----------------------------------------------------- | ---- | ---- | ---- |
| v8               | 3.3 Configure Data Access Control Lists               | \*   | \*   | \*   |
| v7               | 14.6 Protect Information through Access Control Lists | \*   | \*   | \*   |

MITRE ATT&CK Mappings: T1068, T1068.000, T1565, T1565.001, T1565.003 | TA0003 | M1026