$ ping -c1 -p 007ed6a64dfc2bb62a786321a3552b00 pingb.in
 
$ curl pingb.in/p/7ed6a64dfc2bb62a786321a3552b
 
$ dig 7ed6a64dfc2bb62a786321a3552b @pingb.in
 
$ dig 7ed6a64dfc2bb62a786321a3552b.ns.pingb.in
 
C:\> nslookup 7ed6a64dfc2bb62a786321a3552b pingb.in
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://pingb.in/p/7ed6a64dfc2bb62a786321a3552b">]>
    <foo>&xxe;</foo>
 
Waiting for ping...