Pwnkit: Local Privilege Escalation in polkit's pkexec
This is a great write-up, and also a great illustration of something that's fundamentally broken in the way Linux and Unix think about security.`suid` binaries exist for a good reason: they allow users to escalate their privilege in limited ways under control of the system. Good, but obviously risky if the user can subvert that control. The offered solution to that risk is where the problem comes in. Developers of suid binaries are just asked to write them really, really carefully. There are some documents to describe how to do it carefully, but they pretty much assume that code can be developed without bugs, as long as we're careful enough. At least initially, there was no help, no tooling, no verification, no testing, nothing. Just real, real careful.Unfortunately, instead of seeing the absurdity of that situation, many people have gone all "no true Scotsman" on it. "If you were a real Unix Developer then you wouldn't make mistakes like that." We don't need no stinking tools, we're Real Programmers.The situation has been improving, but the underlying mechanism is still super popular and here to stay. It's either time to stop pretending that local `root` means anything, or start taking stuff like this much much more seriously. Some people sure are, but it hasn't pervaded the culture yet.