Re: Symlink Vulnerability in GNU libtool <1.5.2

[<jsm () polyomino org uk>]

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From: "Joseph S. Myers" <jsm () polyomino org uk>
Date: Tue, 3 Feb 2004 21:01:50 -0800
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On Fri, 30 Jan 2004, Stefan Nordhausen wrote:

> Solution:
> Updating to libtool 1.5.2 (the current stable release) will eliminate
> the vulnerability. If you want to stick with your old version of libtool
> you can easily fix this bug yourself. In "ltmain.in" (or file "libtool", 
> whichever applies for you) you should replace the line:
>
> if $mkdir -p "$tmpdir" && chmod 700 "$tmpdir"; then :
>
> with
>
> if $mkdir "$tmpdir" && chmod 700 "$tmpdir"; then :

The chmod has a race (that access to the temporary directory could be
gained after it is created but before it is chmoded) - which I pointed out
when I reported this security bug four years ago
<http://www.geocrawler.com/mail/msg.php3?msg_id=3438808&list=405> - so is
of limited security value.  Alexandre Oliva's patch at that time
(<orsnxk8oqu.fsf () garnize lsd ic unicamp br> on libtool-patches) used umask
to avoid that problem, but wasn't committed (an entirely separate patch
was committed under that log message).

-- 
Joseph S. Myers
jsm () polyomino org uk