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

STIG ID: OL09-00-002423  |  SRG: SRG-OS-000433-GPOS-00193 |  Severity: medium |  CCI: CCI-002824 |  Vulnerability Id: V-271761

Vulnerability Discussion

ASLR makes it more difficult for an attacker to predict the location of attack code they have introduced into a process' 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.

Check

Verify that OL 9 is implementing ASLR with the following command:

$ sysctl kernel.randomize_va_space
kernel.randomize_va_space = 2

If "kernel.randomize_va_space" is not set to "2" or is missing, this is a finding.

Fix

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

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

kernel.randomize_va_space = 2

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

$ sudo sysctl --system