RHEL 9 must enable mitigations against processor-based vulnerabilities.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-257795 | RHEL-09-212050 | SV-257795r1044845_rule | CCI-000381 | low |
| Description | ||||
| Kernel page-table isolation is a kernel feature that mitigates the Meltdown security vulnerability and hardens the kernel against attempts to bypass kernel address space layout randomization (KASLR). Satisfies: SRG-OS-000433-GPOS-00193, SRG-OS-000095-GPOS-00049 | ||||
| STIG | Date | |||
| Red Hat Enterprise Linux 9 Security Technical Implementation Guide | 2025-05-14 | |||
Details
Check Text (C-257795r1044845_chk)
Verify RHEL 9 enables kernel page-table isolation with the following command:
$ sudo grubby --info=ALL | grep args | grep -v 'pti=on'
If any output is returned, this is a finding.
Check that kernel page-table isolation is enabled by default to persist in kernel updates:
$ grep pti /etc/default/grub
GRUB_CMDLINE_LINUX="pti=on"
If "pti" is not set to "on", is missing or commented out, this is a finding.
Fix Text (F-61460r925371_fix)
Configure RHEL 9 to enable kernel page-table isolation with the following command:
$ sudo grubby --update-kernel=ALL --args="pti=on"
Add or modify the following line in "/etc/default/grub" to ensure the configuration survives kernel updates:
GRUB_CMDLINE_LINUX="pti=on"