The Photon operating system must restrict access to the kernel message buffer.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-258828 | PHTN-40-000067 | SV-258828r933545_rule | CCI-001090 | medium |
| 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. | ||||
| STIG | Date | |||
| VMware vSphere 8.0 vCenter Appliance Photon OS 4.0 Security Technical Implementation Guide | 2023-10-29 | |||
Details
Check Text (C-258828r933545_chk)
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 Text (F-62477r933544_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.