1.1.2.2.3 Ensure nosuid option set on /dev/shm partition

Information

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

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

Solution

- IF - a separate partition exists for /dev/shm

Edit the /etc/fstab file and add nosuid to the fourth field (mounting options) for the /dev/shm partition. See the fstab(5) manual page for more information.

Example:

tmpfs /dev/shm tmpfs defaults,rw,nosuid,nodev,noexec,relatime 0 0

Run the following command to remount /dev/shm with the configured options:

# mount -o remount /dev/shm

Note: It is recommended to use tmpfs as the device/filesystem type as /dev/shm is used as shared memory space by applications.

See Also

https://workbench.cisecurity.org/benchmarks/18959