Re: "passwd -F" vulnerability?
Pat Myrto (rwing!pat@ole.cdac.com)
Tue, 10 May 94 16:15:56 PDT
"In the previous message, Mike Raffety said..."
>
> On some Unix systems (e.g., SunOS 4.x), passwd has a "-F" flag allowing
> you to specify the file to use (instead of /etc/passwd). It appears
> that the passwd program pays no attention to permissions on that file;
> it runs setuid to root (of course), and accesses the file without doing
> any permission checking.
So what? One can copy /etc/passwd and edit it with an EDITOR. So?
Login reads /etc/passwd, not whatever file the user chooses. Until
the user can write the changes into /etc/passwd (and sometimes
/etc/security/passwd.adjunct), he has accomplished NOTHING.
Remeber, the passwd command does not determine account access.
[ ... ]
> I've just figured this out; is it a well-known bug? Are there any
> other consequences?
Its not a problem.
--
pat@rwing [If all fails, try: rwing!pat@ole.cdac.com] Pat Myrto - Seattle WA
"No one has the right to destroy another person's belief by demanding
empirical evidence." -- Ann Landers, nationally syndicated advice columnist
and Director at Handgun Control Inc.