Re: /dev/{km,m}em worries

[long-morrow () cs yale edu (H Morrow Long)]

Rick Tait <rickt () gnu ai mit edu> wrote:
> What exactly are the problems with having /dev/mem and /dev/kmem readable
> by other? Is there any way in which our systems can be exploited by 
> this? I recently noticed that one of our (two) servers had a
> different perm on the abovementioned files. Cf:

You (or someone else more malevolent) could read the address space of
processes looking for passwords stored in memory or other interesting
information (ie. a fishing expedition).

A more focused effort would be one of the legendary "clist peekers"
(programs to target for reading the data structures used by the Unix
terminal interfaces - ttys - called 'clists') so that the characters
being typed by users could be read as they were being entered.  Fun!

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H. Morrow Long, Mgr of Dev., Yale Univ., Comp Sci Dept, 011 AKW, New Haven, CT
06520-8285,     VOICE:  (203)-432-{1248,1254}           FAX:    (203)-432-0593