Lack of GUI Isolation as Linux security flaw

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in security on (#3J4)
Here's a little something to sour your morning coffee with the acid taste of anxiety: an interesting piece by Joanna Rutkowska pointing out what she claims is an inherent security flaw in the X Window GUI model :
... Start another terminal window, and switch to root (e.g. using su, or sudo). Notice how the xinput running as user is able to sniff all your keystrokes, including root password (for su), and then all the keystrokes you enter in your root session. Start some GUI app as root, or as different user, again notice how your xinput can sniff all the keystrokes you enter to this other app!

I never knew this and am not aware of much discussion going on about the issue. Is this a fundamental flaw that Windows Vista addresses more successfully, as the author claims, or has the time truly come to do away with the X Window model and develop something else? Did the UNIX-Haters Handbook get this one right?

Not new (Score: 4, Interesting)

by tristram@pipedot.org on 2014-04-18 17:01 (#14B)

This sort of thing has been known for a very long time -- for instance, the reason why most modern login managers restart the X server when you log out is to prevent somebody from leaving a program running that can access the next user's screen or keystrokes. Since the X Window protocol allows applications to find out about keypress events, it's not surprising that if you can run an arbitrary application then you can run a keylogger.

There are lots of keyloggers available for Windows, too; I'm not sure why the author thinks that this is somehow Linux-specific. She obviously is pushing her pet "Qubes OS" project.
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