4.1.2.4 Ensure audit_backlog_limit is sufficient

Information

The backlog limit has a default setting of 64

Rationale:

During boot if audit=1, then the backlog will hold 64 records. If more that 64 records are created during boot, auditd records will be lost and potential malicious activity could go undetected.

Solution

Edit /etc/default/grub and add audit_backlog_limit=<BACKLOG SIZE> to GRUB_CMDLINE_LINUX:
Example:

GRUB_CMDLINE_LINUX='audit_backlog_limit=8192'

Run the following command to update the grub2 configuration:

# grub2-mkconfig -o /boot/grub2/grub.cfg

See Also

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

Item Details

Category: AUDIT AND ACCOUNTABILITY, SYSTEM AND INFORMATION INTEGRITY

References: 800-53|AU-2, 800-53|AU-8, 800-53|AU-12, 800-53|SI-5, CSCv7|6.2, CSCv7|6.3

Plugin: Unix

Control ID: f6aab0fba99cae5dd139d54be12c55b167b5128295a2b7c0fa9df3770ed9838d