The Photon operating system must restrict access to the kernel message buffer.
Severity | Group ID | Group Title | Version | Rule ID | Date | STIG Version |
|---|---|---|---|---|---|---|
| medium | V-258828 | SRG-OS-000138-GPOS-00069 | PHTN-40-000067 | SV-258828r958524_rule | 2024-07-11 | 2 |
Description
Restricting access to the kernel message buffer limits access only to root. This prevents attackers from gaining additional system information as a nonprivileged user.
ℹ️ Check
At the command line, run the following command to verify kernel message buffer restrictions are enabled:
# /sbin/sysctl kernel.dmesg_restrict
Example result:
kernel.dmesg_restrict = 1
If the "kernel.dmesg_restrict" kernel parameter is not set to "1", this is a finding.
✔️ Fix
Navigate to and open:
/etc/sysctl.d/zz-stig-hardening.conf
Add or update the following line:
kernel.dmesg_restrict = 1
At the command line, run the following command to load the new configuration:
# /sbin/sysctl --load /etc/sysctl.d/zz-stig-hardening.conf
Note: If the file zz-stig-hardening.conf does not exist, it must be created.