RHEL 8 must implement address space layout randomization (ASLR) to protect its memory from unauthorized code execution.

STIG ID: RHEL-08-010430  |  SRG: SRG-OS-000433-GPOS-00193 | Severity: medium |  CCI: CCI-002824

Vulnerability Discussion

Some adversaries launch attacks with the intent of executing code in non-executable regions of memory or in memory locations that are prohibited. Security safeguards employed to protect memory include, for example, data execution prevention and address space layout randomization. Data execution prevention safeguards can be either hardware-enforced or software-enforced with hardware providing the greater strength of mechanism.

Examples of attacks are buffer overflow attacks.

Check

Verify RHEL 8 implements ASLR with the following command:

$ sudo sysctl kernel.randomize_va_space

kernel.randomize_va_space = 2

If nothing is returned, verify the kernel parameter "randomize_va_space" is set to "2" with the following command:

$ sudo cat /proc/sys/kernel/randomize_va_space

2

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

Fix

Configure the operating system to implement virtual address space randomization.

Set the system to the required kernel parameter by adding the following line to "/etc/sysctl.d/*.conf"(or modify the line to have the required value):

kernel.randomize_va_space=2

Issue the following command to make the changes take effect:

$ sudo sysctl --system