A couple ways to prevent X11 keylogging/screenshots/actions:
* If chrome/chromium are doing it right now, most parts of the browser should not be able to access X11 directly.
* X.org provides for two compartiments, trusted X (the default) and untrusted X (now used by ssh -X, also sux --untrusted). There are still a number of applications having issues with untrusted X (e.g. Skype doesn't work), also copy & paste don't normally work (for that you can use "xsel -o | ssh otheruser@localhost 'DISPLAY=:1 xsel -i'" or converse, bound to a key combination or panel widget), but it works well enough that I'm running Twinkle and xchat that way.
* let the apps go through VNC (Skype has issues with this, too, though, but then Skype doesn't run smoothly in a VM either (realtime audio issues))
Of course the kernel (and suid apps and apps with tempfile races etc.) are still offering a broader attack surface than a VM, so the above should be complemented with some good intrusion detection mechanism (to catch intrusions before they exploit root), for which I don't have a good suggestion.
* If chrome/chromium are doing it right now, most parts of the browser should not be able to access X11 directly.
* X.org provides for two compartiments, trusted X (the default) and untrusted X (now used by ssh -X, also sux --untrusted). There are still a number of applications having issues with untrusted X (e.g. Skype doesn't work), also copy & paste don't normally work (for that you can use "xsel -o | ssh otheruser@localhost 'DISPLAY=:1 xsel -i'" or converse, bound to a key combination or panel widget), but it works well enough that I'm running Twinkle and xchat that way.
* let the apps go through VNC (Skype has issues with this, too, though, but then Skype doesn't run smoothly in a VM either (realtime audio issues))
Of course the kernel (and suid apps and apps with tempfile races etc.) are still offering a broader attack surface than a VM, so the above should be complemented with some good intrusion detection mechanism (to catch intrusions before they exploit root), for which I don't have a good suggestion.