STIGUI
V-271735CAT III — Low severitySV-271735r1091917_rule

OL 9 must enable mitigations against processor-based vulnerabilities.

Rule version OL09-00-002391 · STIG v1 · 2026-08-21

Discussion

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

Check

Verify that OL 9 enables kernel page-table isolation with the following command:

$ sudo grubby --info=ALL | grep pti args="ro crashkernel=auto resume=/dev/mapper/ol-swap rd.lvm.lv=ol/root rd.lvm.lv=ol/swap rhgb quiet fips=1 audit=1 audit_backlog_limit=8192 pti=on

If the "pti" entry does not equal "on", or is missing, this is a finding.

Check that kernel page-table isolation is enabled by default to persist in kernel updates:

$ sudo 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

Configure OL 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"

Identifiers

Group ID
V-271735
Group title
SRG-OS-000433-GPOS-00193
Rule ID
SV-271735r1091917_rule
Check ID
C-75785r1091915_chk
Fix ID
F-75692r1091916_fix