# CIS Ubuntu 14.04 LTS - 1.1.4 Ensure nosuid option set on /tmp partition

> Ensure nosuid option is set on /tmp partition to prevent setuid file creation

- Skill: `cyberstrikeus/cis-ubuntu-14-04-lts-1-1-4-ensure-nosuid-option-set-on-tmp-p` (Agent Skill)
- Install (CLI): `npx skillmds@latest add cyberstrikeus/cis-ubuntu-14-04-lts-1-1-4-ensure-nosuid-option-set-on-tmp-p`
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- Safety review: PASS (external: skill-scanner PASS, skillspector PASS)
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- Category: Coding & Dev Tools
- Author: cyberstrikeus (https://skillmd.com/u/cyberstrikeus)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/cyberstrikeus/cis-ubuntu-14-04-lts-1-1-4-ensure-nosuid-option-set-on-tmp-p

---


# 1.1.4 Ensure nosuid option set on /tmp partition (Scored)

## Profile Applicability

- Level 1 - Server
- Level 1 - Workstation

## Description

The nosuid mount option specifies that the filesystem cannot contain setuid files.

## Rationale

Since the /tmp filesystem is only intended for temporary file storage, set this option to ensure that users cannot create setuid files in /tmp.

## Audit Procedure

```bash
mount | grep /tmp
# Verify that the nosuid option is set on /tmp
# Expected output: tmpfs on /tmp type tmpfs (rw,nosuid,nodev,noexec,relatime)
```

## Expected Result

The output should show the `nosuid` option is set for the /tmp partition.

## Remediation

```bash
# Edit the /etc/fstab file and add nosuid to the fourth field (mounting options)
# for the /tmp partition. See the fstab(5) manual page for more information.

# Run the following command to remount /tmp:
mount -o remount,nosuid /tmp
```

## Default Value

By default, the nosuid option is not set on /tmp.

## References

- CIS Ubuntu Linux 14.04 LTS Benchmark v2.1.0

## Notes

systemd includes the tmp.mount service which should be used instead of configuring /etc/fstab. Mounting options are configured in the Options setting in /etc/systemd/system/tmp.mount.

## Profile

- Level 1