1.1.10 Ensure separate partition exists for /var

Information

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.



Note: When modifying /var it is advisable to bring the system to emergency mode (so auditd is not running), rename the existing directory, mount the new file system, and migrate the data over before returning to multiuser mode.

Rationale:

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.

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.

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.

See Also

https://workbench.cisecurity.org/files/3682

Item Details

Category: CONFIGURATION MANAGEMENT, IDENTIFICATION AND AUTHENTICATION

References: 800-53|CM-1, 800-53|CM-2, 800-53|CM-6, 800-53|CM-7, 800-53|IA-5, CSCv7|5.1

Plugin: Unix

Control ID: be9f48cc0929ba9d12462308cc3a9f967ba616ad5bf67176b0d0359467915f0f