Well, the other posters who called it a Torx were almost on the mark. What you have there is a Torx Plus which is marketed as a tamper resistant screw and this time Textron has put some actual controls upon the distribution of the tools needed to work properly with them. Guess they learned that everyone and their brother was selling the regular six-pointed Torx tools thus depriving them of any security benefits. Same thing with the Tamper Torx which was identical but which had a pin in the center of the star but which, once the pin was snapped off or the tool had a hole drilled in the tip, was easily removed.
If you want to buy Torx Plus tools you must, in theory anyway, be a legitimate user as defined by Textron although if you know anyone who works with them they should be pretty easily obtained at the cost of a case of beer. ;-)