Well one heuristic to look at is how much proprietary and closed-source software is out there, and then make a rough estimate, say 3% of proprietary software ha

Well one heuristic to look at is how much proprietary and closed-source software is out there, and then make a rough estimate, say 3% of proprietary software has some sort of backdoor or malicious payload in it. What you have to ask, is why is certain software proprietary? Most of it is innocent, but sometimes it's closed for evil reasons.