OL 9 must restrict exposed kernel pointer addresses access.
Severity | Group ID | Group Title | Version | Rule ID | Date | STIG Version |
|---|---|---|---|---|---|---|
| medium | V-271747 | SRG-OS-000132-GPOS-00067 | OL09-00-002408 | SV-271747r1117266_rule | 2026-02-17 | 1 |
Description
Exposing kernel pointers (through procfs or "seq_printf()") exposes kernel writeable structures, which may contain functions pointers. If a write vulnerability occurs in the kernel, allowing write access to any of this structure, the kernel can be compromised. This option disallows any program without the CAP_SYSLOG capability to get the addresses of kernel pointers by replacing them with "0".
Satisfies: SRG-OS-000132-GPOS-00067, SRG-OS-000433-GPOS-00192
ℹ️ Check
Verify that OL 9 restricts access to exposed kernel pointers with the following command:
$ sysctl kernel.kptr_restrict
kernel.kptr_restrict = 1
✔️ Fix
Configure OL 9 to prevent the leak of kernel pointers to unprivileged users.
Add or edit the following line in /etc/sysctl.d/99-sysctl.conf system configuration file:
kernel.kptr_restrict = 1
Reload settings from all system configuration files with the following command:
$ sudo sysctl --system