cis-ubuntu1204-v110-2-13

name	cis-ubuntu1204-v110-2-13
description	Add nosuid Option to Removable Media Partitions
category	cis-os-hardening
version	1.1.0
author	cyberstrike-official
tags	["cis","ubuntu",12.04,"linux","filesystem","removable-media","nosuid","mount-options"]
cis_id	2.13
cis_benchmark	CIS Ubuntu 12.04 LTS Server Benchmark v1.1.0
tech_stack	["ubuntu","linux"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

2.13 Add nosuid Option to Removable Media Partitions (Not Scored)

Profile Applicability

• Level 1

Description

Set nosuid on removable media to prevent setuid and setgid executable files that are on that media from being executed as setuid and setgid.

Rationale

Setting this option on a file system prevents users from introducing privileged programs onto the system and allowing non-root users to execute them.

Audit Procedure

Using Command Line

grep <each removable media mountpoint> /etc/fstab

Verify that nosuid is an option.

Expected Result

The nosuid option should be present in the mount options for each removable media mountpoint.

Remediation

Using Command Line

Edit the /etc/fstab file and add nosuid to the fourth field (mounting options). Look for entries that have mount points that contain words such as floppy or cdrom. See the fstab(5) manual page for more information.

Default Value

By default, the nosuid option is not set on removable media partitions.

References

• CIS Ubuntu 12.04 LTS Server Benchmark v1.1.0

Profile

Level 1 - Not Scored