1.1.17 Ensure noexec option set on /dev/shm partition

Information

The noexec mount option specifies that the filesystem cannot contain executable binaries.

Rationale:

Setting this option on a file system prevents users from executing programs from shared memory. This deters users from introducing potentially malicious software on the system.

Solution

Edit the /etc/fstab file and add noexec to the fourth field (mounting options) for the /dev/shm partition. See the fstab(5) manual page for more information.
Run the following command to remount /dev/shm:

# mount -o remount,noexec /dev/shm

Notes:

Some distributions mount /dev/shm through other means and require /dev/shm to be added to /etc/fstab even though it is already being mounted on boot. Others may configure /dev/shm in other locations and may override /etc/fstab configuration. Consult the documentation appropriate for your distribution.

See Also

https://workbench.cisecurity.org/files/2611