An anonymous reader writes: A new report [http://www.gao.gov/assets/670/669627.pdf] from the U.S. Government Accountability Office (GAO) warns that the increasing uptake of Wi-Fi on commercial flights opens the possibility for attackers to take over the avionics control of a passenger plane. The report states that "the presence of personal smart phones and tablets in the cockpit increases the risk of a system’s being compromised by trusted insiders, both malicious and non-malicious, if these devices have the capability to transmit information to aircraft avionics systems," and notes that the fact that the passenger network is ring-fenced from cockpit avionics by a firewall does not necessarily provide protection from a cyber-hijack; one security professional the GAO approached said "Internet connectivity in the cabin should be considered a direct link between the aircraft and the outside world, which includes potential malicious actors,"