How To Stop DNSMasq from listening on all IPs/Interfaces and allow only localhost
Some people find it less than intuitive to do on DNSMasq and by default DNSMasq is available on 0.0.0.0 which could even be your LAN or Public IP.
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp ........