So you want to prevent a particular program from accessing the internet? Perhaps apparmor is the way to go, see https://apparmor.wiki.kernel.org/index.php/QuickProfileLanguage#Network_Rules
So you want to prevent a particular program from accessing the internet? Perhaps apparmor is the way to go, see https://apparmor.wiki.kernel.org/index.php/QuickProfileLanguage#Network_Rules