The Red Hat Enterprise Linux operating system must implement virtual address space randomization.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-204584	RHEL-07-040201	SV-204584r880794_rule		Medium

Description
Address space layout randomization (ASLR) makes it more difficult for an attacker to predict the location of attack code he or she has introduced into a process's address space during an attempt at exploitation. Additionally, ASLR also makes it more difficult for an attacker to know the location of existing code in order to repurpose it using return-oriented programming (ROP) techniques.

STIG	Date
Red Hat Enterprise Linux 7 Security Technical Implementation Guide	2022-12-06

Details

Check Text ( C-4708r880792_chk )
Verify the operating system implements virtual address space randomization. # grep -r kernel.randomize_va_space /run/sysctl.d/* /etc/sysctl.d/* /usr/local/lib/sysctl.d/* /usr/lib/sysctl.d/* /lib/sysctl.d/* /etc/sysctl.conf 2> /dev/null kernel.randomize_va_space = 2 If "kernel.randomize_va_space" is not configured in the /etc/sysctl.conf file or or in any of the other sysctl.d directories, is commented out or does not have a value of "2", this is a finding. Check that the operating system implements virtual address space randomization with the following command: # /sbin/sysctl -a \| grep kernel.randomize_va_space kernel.randomize_va_space = 2 If "kernel.randomize_va_space" does not have a value of "2", this is a finding. If conflicting results are returned, this is a finding.

Check Text ( C-4708r880792_chk )

Verify the operating system implements virtual address space randomization.

# grep -r kernel.randomize_va_space /run/sysctl.d/* /etc/sysctl.d/* /usr/local/lib/sysctl.d/* /usr/lib/sysctl.d/* /lib/sysctl.d/* /etc/sysctl.conf 2> /dev/null
kernel.randomize_va_space = 2

If "kernel.randomize_va_space" is not configured in the /etc/sysctl.conf file or or in any of the other sysctl.d directories, is commented out or does not have a value of "2", this is a finding.

Check that the operating system implements virtual address space randomization with the following command:

# /sbin/sysctl -a | grep kernel.randomize_va_space
kernel.randomize_va_space = 2

If "kernel.randomize_va_space" does not have a value of "2", this is a finding.

If conflicting results are returned, this is a finding.

Fix Text (F-4708r880793_fix)
Configure the operating system implement virtual address space randomization. Set the system to the required kernel parameter by adding the following line to "/etc/sysctl.conf" or a config file in the /etc/sysctl.d/ directory (or modify the line to have the required value): kernel.randomize_va_space = 2 Issue the following command to make the changes take effect: # sysctl --system