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V-271766

CAT II (Medium)

OL 9 must prevent the loading of a new kernel for later execution.

Rule ID

SV-271766r1092010_rule

STIG

Oracle Linux 9 Security Technical Implementation Guide

Version

V1R5

CCIs

CCI-003992

Discussion

Changes to any software components can have significant effects on the overall security of the operating system. This requirement ensures the software has not been tampered with and that it has been provided by a trusted vendor. Disabling kexec_load prevents an unsigned kernel image (that could be a windows kernel or modified vulnerable kernel) from being loaded. Kexec can be used subvert the entire secureboot process and should be avoided at all costs especially since it can load unsigned kernel images.

Check Content

Verify that OL 9 is configured to disable kernel image loading.

Check the status of the kernel.kexec_load_disabled kernel parameter with the following command:

$ sysctl kernel.kexec_load_disabled
kernel.kexec_load_disabled = 1

If "kernel.kexec_load_disabled" is not set to "1" or is missing, this is a finding.

Fix Text

Configure OL 9 to prevent the loading of a new kernel for later execution.

Add or edit the following line in a system configuration file in the "/etc/sysctl.d/" directory:

kernel.kexec_load_disabled = 1

Load settings from all system configuration files with the following command:

$ sudo sysctl --system