1.1.4 Ensure nosuid option set on /tmp partition

Information

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

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

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 remount /tmp :
# mount -o remount,nosuid /tmp

See Also

https://workbench.cisecurity.org/files/2521

Item Details

Category: ACCESS CONTROL

References: 800-53|AC-6(10), CSCv7|5.1

Plugin: Unix

Control ID: 03192f84b485f2f5763b3e63b01eb04581a30170ba8f6882d47936459095cbd1