Re: Another Mac OS X ScreenSaver Security Issue (after Security Update 2003-07-14)

From: MightyE (trashat_private)
Date: Thu Jul 31 2003 - 12:02:01 PDT

  • Next message: Gavin Hanover: "Re: Another Mac OS X ScreenSaver Security Issue (after Security Update 2003-07-14)"

    If anything I'd call this a security consideration of Escape Pod.  
    Perhaps Escape Pod should try to talk to the process it's about to kill, 
    and get its 'permission' for killing, and failing a timely response (2 
    secs?), drop the program.  ScreenSaverEngine would have to be tailored 
    to respond to such a request.
    
    On Linux, doesn't xscreensaver run as root?  Wouldn't this be another 
    option here (I'm admittedly unfamiliar with Mac OS X), preventing Escape 
    Pod from even being capable of terminating the screensaver process?  Or 
    does Escape Pod also run as root?
    
    If you ask me, Escape Pod owes it to their users to develop the product 
    in such a way so to not nullify reasonable security measures on the part 
    of the OS, even if that's an option to never terminate processes named 
    ScreenSaverEngine.
    
    -MightyE
    
    Alaric B Snell wrote:
    
    > Rizwan Jiwan wrote:
    >
    >> I wouldn't consider this a bug. It is like me writing a script that 
    >> kills
    >> any process named "ScreenSaverEngine". If I run it with my privileges it
    >> should allow me to kill the process (assuming I own ScreenSaverEngine).
    >> Escape Pod does what it is meant to. OS X does what it is meant 
    >> to--that is
    >> unless you are suggesting that the operating system not allow the 
    >> user to
    >> kill the screen saver process which is just stupid because I have had my
    >> screen saver crash on me.
    >
    >
    > Yes. But either way, it looks as if a side effect of Escape Pod is 
    > that it nullifies the security of the screen saver.
    >
    > It sounds like the real issue is that the screensaver - which is meant 
    > to lock the keyboard, mouse, and display device to prevent tampering 
    > by passers-by (who do not have the option of taking the machine home 
    > and mounting the disk in another machine et al). The flaw seems to be 
    > in that the OS is still passing keyboard events to the likes of Escape 
    > Pod when the screensaver has asked to lock the keyboard. Maybe it's 
    > the screen saver's fault, in that it's not properly locking the 
    > keyboard, but it's more likely to be that the code in the GUI that 
    > handles locking the console should disable 'hotkey' processing too.
    >
    >>
    >> -Riz
    >>
    >
    > ABS
    >
    



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