OL 9 must implement address space layout randomization (ASLR) to protect its memory from unauthorized code execution.

ASLR makes it more difficult for an attacker to predict the location of attack code they have introduced into a process's address space during an attempt at exploitation. Additionally, ASLR makes it more difficult for an attacker to know the location of existing code to repurpose it using return-oriented programming (ROP) techniques.

Verify that OL 9 is implementing ASLR with the following command: $ sysctl kernel.randomize_va_space kernel.randomize_va_space = 2 Check that the configuration files are present to enable this kernel parameter: $ sudo grep -rs kernel.randomize_va_space /run/sysctl.d/*.conf /usr/local/lib/sysctl.d/*.conf /usr/lib/sysctl.d/*.conf /lib/sysctl.d/*.conf /etc/sysctl.conf /etc/sysctl.d/*.conf /etc/sysctl.d/99-kernel_randomize_va_space.conf:kernel.randomize_va_space = 2 If "kernel.randomize_va_space" is not set to "2", or is missing, this is a finding. If conflicting results are returned, this is a finding.

Configure OL 9 to implement ASLR to protect its memory from unauthorized code execution. Add the configuration item with the following command: $ echo 'kernel.randomize_va_space = 2' | sudo tee /etc/sysctl.d/99-kernel_randomize_va_space.conf Remove any configurations that conflict with the above from the following locations: /run/sysctl.d/*.conf /usr/local/lib/sysctl.d/*.conf /usr/lib/sysctl.d/*.conf /lib/sysctl.d/*.conf /etc/sysctl.conf /etc/sysctl.d/*.conf Reload settings from all system configuration files with the following command: $ sudo sysctl --system