Details
The /var directory is used by daemons and other system services to temporarily store dynamic data. Some directories created by these processes may be world-writable. Since the /var directory may contain world-writable files and directories, there is a risk of resource exhaustion if it is not bound to a separate partition.
Solution
For new installations, during installation create a custom partition setup and specify a separate partition for /var. For systems that were previously installed, create a new partition and configure /etc/fstab as appropriate. Impact: Resizing filesystems is a common activity in cloud-hosted servers. Separate filesystem partitions may prevent successful resizing, or may require the installation of additional tools solely for the purpose of resizing operations. The use of these additional tools may introduce their own security considerations.
Supportive Information
The following resource is also helpful.
This security hardening control applies to the following category of controls within NIST 800-53: Configuration Management.This control applies to the following type of system Unix.