# Cis Ubuntu2004 V300 1 1 2 2 2

> Ensure nodev option set on /dev/shm partition

- Skill: `cyberstrikeus/cis-ubuntu2004-v300-1-1-2-2-2` (Agent Skill)
- Install (CLI): `npx skillmds@latest add cyberstrikeus/cis-ubuntu2004-v300-1-1-2-2-2`
- Raw SKILL.md: https://api.skillmd.com/api/skills/cyberstrikeus/cis-ubuntu2004-v300-1-1-2-2-2/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-ubuntu2004-v300-1-1-2-2-2

---


# Ensure nodev option set on /dev/shm partition

## Profile

Level 1 - Server, Level 1 - Workstation, Assessment: Automated

## Description

The `nodev` mount option specifies that the filesystem cannot contain special devices.

## Rationale

Since the `/dev/shm` filesystem is not intended to support devices, set this option to ensure that users cannot attempt to create special devices in `/dev/shm` partitions.

## Audit Procedure

### Command Line

- IF - a separate partition exists for `/dev/shm`, verify that the `nodev` option is set.

```bash
# findmnt -kn /dev/shm | grep -v 'nodev'
```

Nothing should be returned

## Expected Result

Nothing should be returned

## Remediation

### Command Line

- IF - a separate partition exists for `/dev/shm`.
  Edit the `/etc/fstab` file and add `nodev` to the fourth field (mounting options) for the `/dev/shm` partition. See the `fstab(5)` manual page for more information.
  Example:

```
tmpfs /dev/shm   tmpfs   defaults,rw,nosuid,nodev,noexec,relatime   0 0
```

Run the following command to remount `/dev/shm` with the configured options:

```bash
# mount -o remount /dev/shm
```

Note: It is recommended to use `tmpfs` as the device/filesystem type as `/dev/shm` is used as shared memory space by applications.

## Default Value

Not configured by default.

## References

1. NIST SP 800-53 Rev. 5: AC-3, MP-2
2. NIST SP 800-53 Revision 5 :: CM-7 (2)
3. RHEL 8 STIG Vul ID: V-230508
4. RHEL 8 STIG Rule ID: SV-230508r854049

## CIS Controls

v8 - 3.3 Configure Data Access Control Lists (IG 1, IG 2, IG 3)
v7 - 14.6 Protect Information through Access Control Lists (IG 1, IG 2, IG 3)

MITRE ATT&CK Mappings: T1200, T1200.000 | TA0005 | M1022