if you don't care about unicode domains then mitigation can be very simple using dnsmasq, e.g.:

in /etc/dnsmasq.conf add something like:

  # Add domains which you want to force to an IP address here.
  address=/:xn--*:/0.0.0.0

(in case your dnsmasq doesn't support this then there is a patch here: https://github.com/spacedingo/dnsmasq-regexp_2.76)