Vulnerability Discussion

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.

Check

Verify RHEL 8 restricts exposed kernel pointer addresses access with the following commands:

$ sudo sysctl kernel.kptr_restrict

kernel.kptr_restrict = 1

If the returned line does not have a value of "1", or a line is not returned, this is a finding.

Fix

Configure RHEL 8 to restrict exposed kernel pointer addresses access by adding the following line to a file in the "/etc/sysctl.d" directory:

kernel.kptr_restrict = 1

The system configuration files need to be reloaded for the changes to take effect. To reload the contents of the files, run the following command:

$ sudo sysctl --system