# CIS Ubuntu 14.04 LTS - 1.1.1.1 Ensure mounting of cramfs filesystems is disabled

> Ensure the cramfs filesystem type is disabled to reduce attack surface

- Skill: `cyberstrikeus/cis-ubuntu-14-04-lts-1-1-1-1-ensure-mounting-of-cramfs-files` (Agent Skill)
- Install (CLI): `npx skillmds@latest add cyberstrikeus/cis-ubuntu-14-04-lts-1-1-1-1-ensure-mounting-of-cramfs-files`
- Raw SKILL.md: https://api.skillmd.com/api/skills/cyberstrikeus/cis-ubuntu-14-04-lts-1-1-1-1-ensure-mounting-of-cramfs-files/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-ubuntu-14-04-lts-1-1-1-1-ensure-mounting-of-cramfs-files

---


# 1.1.1.1 Ensure mounting of cramfs filesystems is disabled (Scored)

## Profile Applicability

- Level 1 - Server
- Level 1 - Workstation

## Description

The cramfs filesystem type is a compressed read-only Linux filesystem embedded in small footprint systems. A cramfs image can be used without having to first decompress the image.

## Rationale

Removing support for unneeded filesystem types reduces the local attack surface of the server. If this filesystem type is not needed, disable it.

## Audit Procedure

```bash
modprobe -n -v cramfs
# Expected output: install /bin/true

lsmod | grep cramfs
# Expected output: <No output>
```

## Expected Result

`modprobe -n -v cramfs` should return `install /bin/true` and `lsmod | grep cramfs` should return no output.

## Remediation

```bash
# Edit or create the file /etc/modprobe.d/CIS.conf and add the following line:
echo "install cramfs /bin/true" >> /etc/modprobe.d/CIS.conf

# Unload the cramfs module:
rmmod cramfs
```

## Default Value

By default, cramfs filesystem mounting is allowed.

## References

- CIS Ubuntu Linux 14.04 LTS Benchmark v2.1.0
- CIS Controls: 13 Data Protection

## Profile

- Level 1