In a claim reminiscent of Oracle Corp.'s "unbreakable" marketing campaign of several years ago, the U.S. military has built what it calls a hack proof drone.The Pentagon's Defense Advanced Research Projects Agency (DARPA) developed the unmanned aerial vehicle under its High-Assurance Cyber Military Systems (HACMS) program, military blog Defense Tech reported last week.DARPA unveiled a prototype of the mini-drone last week during a broader demonstration of over 100 ongoing research projects at the agency.DARPA's HACMS program was created to develop technologies for improving the security of embedded systems in drones, weapons systems, aircraft, supervisory control and data acquisition (SCADA) systems and medical and mobile devices.HACMS is looking especially at interactive software synthesis systems, code verification tools and new specification languages, DARPA said. If the technologies prove successful, DARPA will make them available for use in commercial and defense systems."HACMS will adopt a clean-slate, formal methods-based approach to enable semi-automated code synthesis from executable, formal specifications," DARPA said in a statement. In addition to generating code, HACMS will also develop technology for ensuring that all generated code satisfies security and safety policies.Software developed for the quadcopter drone makes it impervious to attacks by hackers that try to take over its navigation and control systems. "The software is mathematically proven to be invulnerable to large classes of attack," HACMS program manager Kathleen Fisher told Defense Tech.All attempts to hack into the drone during red-team exercises and other penetration tests by cyber security experts failed, she told the military blog site.DARPA did not respond to Computerworld's request for comment on the technology.If the software really works as billed, it would be a big step forward for the Pentagon. Over the past six years, there have been at least two known incidents in which U.S. military drones were apparently being hacked into by attackers.In 2008, insurgents in Iraq claimed they were able to intercept live feeds from U.S. Predator drones using a $26 software tool called SkyGrabber from Russian company SkySoftware.SkyGrabber, designed to intercept music, video and TV satellite programming for free, worked because video transmissions from the drones to grounds control stations were being sent unencrypted.In a more sensational incident in 2011, Iranian electronic warfare experts claimed they had managed to capture a sophisticated RQ-170 Sentinel drone by hacking into its control and navigation system.Iranian engineers claimed they were able to cut off communications links from U.S. ground stations to the Lockheed-Martin-made drone and reconfigure its GPS coordinates to trick it into landing in Iran. According to the engineers, they developed the attack by reverse engineering U.S. drones that had been previously shot down or captured.Though many in the U.S. initially dismissed Iran's claims, later research showed that such an attack was theoretically possible.Jaikumar Vijayan covers data security and privacy issues, financial services security and e-voting for Computerworld. Follow Jaikumar on Twitter at @jaivijayan or subscribe to Jaikumar's RSS feed. His e-mail address is firstname.lastname@example.org.See more by Jaikumar Vijayan on Computerworld.com.Read more about government\/industries in Computerworld's Government\/Industries Topic Center.