Details

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= to GRUB_CMDLINE_LINUX:
Example:

GRUB_CMDLINE_LINUX=’audit_backlog_limit=8192′

Run the following command to update the grub2 configuration:

# update-grub

Supportive Information

The following resource is also helpful.

• https://workbench.cisecurity.org/files/2658

This security hardening control applies to the following category of controls within NIST 800-53: Audit and Accountability.This control applies to the following type of system Unix.

References

• 800-53|AU-3
• 800-53|AU-12
• CSCv7|6.2
• CSCv7|6.3

Source

• Tenable.com/audits