InformationThe /tmp directory is a world-writable directory used for temporary storage by all users and some applications.
Since the /tmp directory is intended to be world-writable, there is a risk of resource exhaustion if it is not bound to a separate partition. In addition, making /tmp its own file system allows an administrator to set the noexec option on the mount, making /tmp useless for an attacker to install executable code. It would also prevent an attacker from establishing a hardlink to a system setuid program and wait for it to be updated. Once the program was updated, the hardlink would be broken and the attacker would have his own copy of the program. If the program happened to have a security vulnerability, the attacker could continue to exploit the known flaw.
SolutionFor new installations, check the box to 'Review and modify partitioning' and create a separate partition for /tmp. For systems that were previously installed, use the Logical Volume Manager (LVM) to create partitions.