Re: Buffer overflow in Explorer.exe
From: Berend-Jan Wever (SkyLined_at_edup.tudelft.nl)
To: <firstname.lastname@example.org> Date: Sun, 11 May 2003 19:55:46 +0200
Could this not be done remotely without user interaction except browsing an
evil website by using SMB ?
You can make IE browse a harddisk which' contents you control...
I don't have XP so I can't test this. Let me know what you find.
----- Original Message -----
From: "Kristopher Matthews" <email@example.com>
To: "'Ryan Yagatich'" <firstname.lastname@example.org>
Sent: Friday, May 09, 2003 18:42
Subject: RE: Buffer overflow in Explorer.exe
I have tested and duplicated this behavior on a fully patched/updated
Windows XP Pro system.
1. The overflow is for that particular key, AFAICT.
1a. It will not work for the root (c:/) directory; explorer.exe does not
parse 'desktop.ini' for that directory. It will, however, work for any other
2. It crashes explorer.exe (which runs the task bar/start menu, etc) - It
looks for all the world like a standard buffer overflow; I believe a more
carefully crafted 'desktop.ini' file could be cause for explorer.exe to
unintentionally execute arbitrary code.
3. Download and execute untrusted code? Combine this with any of the other
popular expoloits for windows; also, it wouldn't be terribly hard to get a
user to download a 'desktop.ini' file to their "My Documents" directory (in
the guise, of, say, a folder them, which windows does support; e.g.
different background, file layout, etc); bam, whenever they open that
directory, explorer crashes.
From: Ryan Yagatich [mailto:email@example.com]
Sent: Thursday, May 08, 2003 6:28 PM
I don't quite understand the purpose behind this code. It creates
a read only file '/aT4r[at]3WDesign.es Security/desktop.ini' with the
And then terminates? I don't have a windows machine available to
really explore this any, but what makes that entry in desktop.ini cause
this? Furthermore, is this issue only for that particular key or is it
generally just key/excessive parameter/missing value size that is
affected? And additionally, you mention that explorer will no longer be
able to operate when trying to browse the hard disk, but does this mean
globally, or when they try to browse the c:/ drive, or just that
Please send me more information about this, (even if it references
past posts that I have missed) so that I can better understand the
severity of this. Espcially since to me, I still see it as someone needing
to download and execute untrusted software which causes a system crash,
and if that were going to happen there are far worse things that can be
done besides creating a small text file.
\ Ryan Yagatich firstname.lastname@example.org \
/ Pantek Incorporated (877) LINUX-FIX /
\ http://www.pantek.com/security (440) 519-1802 \
/ Are your networks secure? Are you certain? /
On Wed, 7 May 2003, aT4r InsaN3 wrote:
>This bug allow a malicious an attacker to execute data with privileges of a
>user that is browsing the hard disk with explorer.
>tested against winxp SP1
>example code provided.
> strcpy(path,"\\aT4r[at]3WDesign.es Security");