Information
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.
Solution
IF /etc/fstab is used to mount /tmp
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
OR if systemd is used to mount /tmp:
Edit /etc/systemd/system/local-fs.target.wants/tmp.mount to add nosuid to the /tmp mount options:
[Mount]
Options=mode=1777,strictatime,noexec,nodev,nosuid
Run the following command to restart the systemd daemon:
# systemctl daemon-reload
Run the following command to restart tmp.mount:
# systemctl restart tmp.mount
Item Details
Category: ACCESS CONTROL, CONFIGURATION MANAGEMENT, MEDIA PROTECTION, SYSTEM AND SERVICES ACQUISITION
References: 800-53|AC-3, 800-53|AC-5, 800-53|AC-6, 800-53|CM-2, 800-53|CM-6, 800-53|CM-7, 800-53|CM-7(1), 800-53|CM-9, 800-53|MP-2, 800-53|SA-3, 800-53|SA-8, 800-53|SA-10, CSCv7|5.1
Control ID: 379d558d47f1e8a5da660f458383a277f22a5d8ee69f8fff8edf5d3676981131