[ Resubmitting - I think the original post did not go through last week, but some of the responses did, so probably an accident. ] --- I think we greatly underappreciate the extent to which JavaScript allows you to exploit the limits of human perception. On modern high-performance systems, windows can be opened, positioned, and closed; and documents loaded and then navigated away from; so quickly that we can't even reliably notice that, let alone react consciously. The PoC I posted here earlier this week (http://lcamtuf.coredump.cx/switch/) demonstrates one example of page transitions occurring so fast that you don't register it; and some of my earlier posts outlined the exploitation of page switching to exploit browser UIs (e.g. http://lcamtuf.coredump.cx/ffgeo2/). Today, I wanted to share this brief demonstration of an attack that should hopefully illustrate why our current way of thinking about clickjacking (and the possible defenses, such as X-Frame-Options) is flawed: http://lcamtuf.coredump.cx/clickit/ The basic idea here is that instead of placing the UI you want to tamper with in an invisible or only partly-visible <iframe>, you can achieve a similar effect simply by predicting the time of a premeditated click (which is fairly easy if you look at mouse velocity and distance to the expected destination), and then either destroying the current window, or navigating to a different document (in this case, a cheesy banking site). While everything about this exploit is extremely goofy, and I put no effort into making the transitions less obvious, it should still demonstrate the issue neatly. /mz
