IBM thinkpad boot sequence insecurity

From: Pavel Machek (pavelat_private)
Date: Sun Feb 21 1999 - 10:20:25 PST

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    Hi!
    
       IBM gave me Thinkpad 560X notebook, about year ago (thanx, it is nice
       beast). I discovered few misfeatures, and few bugs, some of them are
       related to security. Here it goes:
         * Thinkpad will boot from floppy, even if it has boot-up sequence
           set to hard drive first and hard disk is bootable. Floppy has to
           have IBM bootsector for this to work, for example personality
           setting boot disk distributed by IBM has it. I've successfully
           created Linux boot disk, which can be used on Thinkpad with floppy
           booting disabled. If someone relied on boot up sequence for
           security (I believe many people do), you are screwed. (BTW I use
           it now as a feature. Thinkpad will refuse to boot, if their
           self-tests fail (which is pretty bad behaviour: if your trackpoint
           fails, you are not unable to get to critical data stored on your
           thinkpad). Anyway, if you put IBM floppy, it will boot even if
           self-tests failed. So I can at least access my data.
         * Thinkpad will allow people to change personality information, even
           without supervisor password. Thinkpad has "personality" feature
           which allows people to mark their computer with their name,
           address, and picture. I use penguin ;-). Unfortunately, this info
           is changeable even without supervisor password. (And BTW floppy
           which allows you to change it has "magic" format.) This might be
           more severe than it seems, because, IMHO, setting personality
           information means flashing bios. I'm not sure if flashing in
           modified bios is UN-doable.
         * Easy setup - HDD tests. Easy setup is just plain ugly. It looks
           like a perfectly safe thing. Well, it will overwrite part of your
           hard drive without even asking for confirmation. It seems like
           hard drives come preformated to slightly little capacity then they
           really have. The rest is test zone, used for easy setup's rw
           tests. But if you happen to re-fdisk your drive, it is pretty easy
           to put normal partition into this zone (this zone is not
           documented anywhere). This one killed 2000 of your inodes 4 times.
           Last two times was random person coming around my computer, and
           launching tests because machine asked them to do so. Beware!
          [snip]
    
       As a side note, does anyone know if there are seals inside thinkpad
       560X? IBM gave me computer, but they failed to give me warranty. I
       think broken trackpoint should not be _that_ hard to fix ;-).
    
    
    (This is trimmed version of page available at
    http://atrey.karlin.mff.cuni.cz/~pavel/thinkpad.html. I mailed a copy
    IBM week ago, and got no response so far. They had enough time.)
    
    --
    I'm really pavelat_private 	   Pavel
    Look at http://atrey.karlin.mff.cuni.cz/~pavel/ ;-).
    



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