Rule ID
SV-248576r1156619_rule
Version
V2R8
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 to subvert the entire secureboot process and should be avoided at all costs, especially since it can load unsigned kernel images. The sysctl --system command will load settings from all system configuration files. All configuration files are sorted by their filename in lexicographical order, regardless of the directories in which they reside. If multiple files specify the same option, the entry in the file with the lexicographically latest name will take precedence. Files are read from directories in the following list from top to bottom. Once a file of a given filename is loaded, any file of the same name in subsequent directories is ignored. /etc/sysctl.d/*.conf /run/sysctl.d/*.conf /usr/local/lib/sysctl.d/*.conf /usr/lib/sysctl.d/*.conf /lib/sysctl.d/*.conf /etc/sysctl.conf
Note: For OL 8 systems using the Oracle Unbreakable Enterprise Kernel (UEK) Release 6 or above and with secureboot enabled, this requirement is Not Applicable. Verify OL 8 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.
Configure OL 8 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