Arbitary file download vulnerability on a DoD website

Summary

A DoD website was misconfigured in a manner that could have allowed an attacker to collect sensitive information about the web application or system. @psychomantis was able to demonstrate this vulnerability by crafting a specially formatted URL. Thank you for notifying us of this vulnerability!

This website used DotNetNuke EventsCalendar which is prone to an arbitrary-file-download vulnerability. An example of what this looks like is this, website.com/desktopmodules/eventscalendar/downloaddoc.aspx We can exploit this by appending ?f=/downloaddoc.aspx so it'd look like this, website.com/desktopmodules/eventscalendar/downloaddoc.aspx?f=/downloaddoc.aspx