Vulnerability Discussion

To ensure that DNS resolver settings are respected, a DNS mode in Network Manager must be configured.

Check

Verify that OL 9 has a DNS mode configured in Network Manager.

$ NetworkManager --print-config
[main]
dns=none

If the DNS key under main does not exist or is not set to "none" or "default", this is a finding.

Fix

Configure NetworkManager in OL 9 to use a DNS mode.

In "/etc/NetworkManager/NetworkManager.conf" add the following line in the "[main]" section:

dns = none

NetworkManager must be reloaded for the change to take effect.

$ sudo systemctl reload NetworkManager