1.1.4 Ensure nosuid option set on /tmp partition (Scored)

Level 1 - Server 
Level 1 - Workstation

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.

If a /tmp partition exists run the following command and verify that the nosuid option is set on /tmp:

# mount | grep /tmp 
tmpfs on /tmp type tmpfs (rw,nosuid,nodev,noexec,relatime)

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

systemd includes the tmp.mount service which should be used instead of configuring /etc/fstab. Mounting options are configured in the Options setting in /etc/systemd/system/tmp.mount.

  • ubuntu1604/1/1/4.txt
  • Last modified: 2017/05/02 14:12
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