OL 8 must disable access to the network "bpf" syscall from unprivileged processes.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-248889	OL08-00-040281	SV-248889r780233_rule		Medium

Description
It is detrimental for operating systems to provide, or install by default, functionality exceeding requirements or mission objectives. These unnecessary capabilities or services are often overlooked and therefore may remain unsecured. They increase the risk to the platform by providing additional attack vectors.

STIG	Date
Oracle Linux 8 Security Technical Implementation Guide	2021-07-21

Details

Check Text ( C-52323r780231_chk )
Verify OL 8 prevents privilege escalation through the kernel by disabling access to the "bpf" syscall with the following commands: $ sudo sysctl kernel.unprivileged_bpf_disabled kernel.unprivileged_bpf_disabled = 1 If the returned line does not have a value of "1" or a line is not returned, this is a finding.

Fix Text (F-52277r780232_fix)
Configure the system to prevent privilege escalation through the kernel by disabling access to the "bpf" syscall by adding the following line to a file in the "/etc/sysctl.d" directory: kernel.unprivileged_bpf_disabled = 1 The system configuration files must be reloaded for the changes to take effect. To reload the contents of the files, run the following command: $ sudo sysctl --system