Our open society is also an open window through which terrorists can gain access to so much information which they can use to harm this country.
Recent events, claims of hacking and an April, 2015 GAO report have highlighted the potential risks of an aircraft to cyberattacks. In response to those warnings the FAA convened a “private meeting” to address the security of these systems. Obviously the sensitivity of this issue is the reason for this non-public review (the group may be empowered by a federal advisory charter). What remains to be seen is the technical scope of their work.