File systems that are being imported via Network File System (NFS) must be mounted to prevent binary files from being executed.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-75581	UBTU-16-010830	SV-90261r2_rule		Medium

Description
The "noexec" mount option causes the system to not execute binary files. This option must be used for mounting any file system not containing approved binary files as they may be incompatible. Executing files from untrusted file systems increases the opportunity for unprivileged users to attain unauthorized administrative access.

STIG	Date
Canonical Ubuntu 16.04 Security Technical Implementation Guide	2020-05-29

Details

Check Text ( C-75285r2_chk )
Verify file systems that are being Network File System (NFS) imported are mounted with the "noexec" option. Find the file system(s) that contain the directories being exported with the following command: # grep nfs /etc/fstab \| grep noexec UUID=e06097bb-cfcd-437b-9e4d-a691f5662a7d /store nfs rw,noexec 0 0 If a file system found in "/etc/fstab" refers to NFS and it does not have the "noexec" option set, and use of NFS exported binaries is not documented with the Information System Security Officer (ISSO) as an operational requirement, this is a finding.

Check Text ( C-75285r2_chk )

Verify file systems that are being Network File System (NFS) imported are mounted with the "noexec" option.

Find the file system(s) that contain the directories being exported with the following command:

# grep nfs /etc/fstab | grep noexec

UUID=e06097bb-cfcd-437b-9e4d-a691f5662a7d /store nfs rw,noexec 0 0

If a file system found in "/etc/fstab" refers to NFS and it does not have the "noexec" option set, and use of NFS exported binaries is not documented with the Information System Security Officer (ISSO) as an operational requirement, this is a finding.

Fix Text (F-82209r2_fix)
Configure the "/etc/fstab" to use the "noexec" option on file systems that are being imported via Network File System (NFS).