Starting with v14.0, the Untangle kernel is version 4.9. However, any Untangle that was upgraded to v14 from v13.2 or older will still have the old 3.16 kernel installed and will only be running on the new 4.9 kernel if you've restarted and chosen the new version. If you need to find out which kernel you're using, you can find it in Config > About:
In most cases, only the major & minor versions are relevant. In this example, we could refer to it as simply 'kernel 3.16'.