Silly question; how common is this class of bug? We're talking about an application that lives on the local system, and is probably only exploitable via social engineering bugs (i.e. we convince the user to do something stupid).We live in a world where merely installing software might also install a silent updater in the background, or might interfere with existing software that it has no need to touch, or might start monitoring peripherals and phone home with data in ways that could invade privacy. We also live in a world where once popular software, particularly freely available software, sometimes drifts into borderline malware territory over time. In this world, “doing something stupid” can be as simple as turning on your computer and installing (not running, just installing) some of the most popular software in the world today on it.
What is the problem that sandboxing every app into a homogenous set of thou-shalt-not's solves?
To give a few examples, some of us would consider it a bug for everyday applications to splat junk all over a filesystem during a build/install, or to hide data in odd places as part of a copy protection scheme, or to scan a whole disk and automatically upload any files that might support “cheating” in a game to the mothership.
Unlike some here, I am not willing to trust the good intentions of a software developer just because I have paid good money to use their product. Far too many shady practices go on in parts of our industry for that to be a sensible policy without adequate safeguards in place any more.
