There is a technique called stagefright that can exploit a system by playing a video, but this is not an MPEG problem or any other video format problem. It's a C and C++ problem. Malformed data causes a C or C++ program to behave unexpectedly. The C and C++ languages not only cripple your mind, your operating system, and your hardware, they allow invaders to take over your machine by doing simple things like watching a video or generating thumbnails.
Those are some pretty dumb arguments of course. There is nothing that limits a C program or a C library from implementing those things or the things discussed in this thread. There is nothing about a programming language that will somehow extend the capabilities of a computer any more than a program written on paper will create extra pages in your notebook.
Programming languages can't do anything your computer can't, but they can prevent you from using the capabilities of a computer, and they can prevent you from building new hardware that has additional capabilities.