Correct, security torx.
But when I run into oddball screws that I don't need to save, I use a Dremel with a cutoff bit to cut a slot in the head so I can use a flat head screwdriver to remove it. You could also do this if you wanted to replace the screw with a standard pan head or round head machine screw. Might make it easier in the future if you ever have to take it apart again and don't want to scrounge for a torx security bit.