[CrackMonkey] For your collection

Don Marti dmarti at zgp.org
Tue Jul 18 13:14:34 PDT 2000

Do you collect email headers that have interesting effects on
non-standard or defective clients?  Then this one's for you.

----- Forwarded message from Aaron Drew <ripper at HOTKEY.NET.AU> -----

Date:         Wed, 19 Jul 2000 20:02:27 +1000
From: Aaron Drew <ripper at HOTKEY.NET.AU>
Subject:      Buffer Overflow in MS Outlook Email Clients
Delivered-To: dmarti at zgp.org
Approved-By: aleph1 at SECURITYFOCUS.COM
Delivered-To: bugtraq at lists.securityfocus.com
Delivered-To: bugtraq at securityfocus.com
Importance: Normal
Reply-To: Aaron Drew <ripper at HOTKEY.NET.AU>


Security Advisory: Buffer Overflow in MS Outlook & Outlook Express Email Clients

Date: 			18th July 2000
Author:			Aaron Drew (mailto:ripper at wollongong.hotkey.net.au)
Versions Affected: 	MS Outlook 97/2000 and MS Outlook Express 4/5


A bug in a shared component of Microsoft Outlook and Outlook Express mail
clients can allow a remote user to write arbitrary data to the stack. This
bug has been found to exist in all versions of MS Outlook and Outlook
Express on both Windows 95/98 and Windows NT 4.

The vulnerability lies in the parsing of the GMT section of the date field
in the header of an email. Bound checking on the token representing the GMT
is not properly handled. This bug can be witnessed by opening an email with
an exceptionally long string directly preceding the GMT specification in
the Date header field such as:

Date: Fri, 13 July 2000 14:16:06 +1000xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

The bug lies in the shared library INETCOMM.DLL and has been successfully
exploited on Windows 95, 98 and NT with both Outlook and Outlook Express.

The execution of this code is performed differently under each client. Under
Outlook Express, the buffer overflow occurs as soon as the user tries to
view the mail folder containing email with a malicious date header. Under
Microsoft Outlook, the overflow occurs when attempting to preview, read,
reply or forward any email with a malicious date header. Under MS Outlook a
user may delete or save an email to disk without exploitation.

Whilst some mail transport systems seem to modify 8-bit header data or lines
over 70 characters in length preventing direct exploitation, these
restrictions seem to be avoided by encoding a message with an exploit date
field as a MIME attachment in a Outlook's MIME attached message format.
These messages also overflow the stack when read, previewed, replied to or

Microsoft was notified of this bug on July 3.

Attached is a proof-of-point exploit that, when placed in the header
field of a message or MIME attached message, will download and execute
an executable from the web. (In this particular case it will launch MS Freecell)



The information within this document may change without notice. Use of
this information constitutes acceptance for use in an AS IS
condition. There are NO warranties with regard to this information.
In no event shall the author be liable for any consequences whatsoever
arising out of or in connection with the use or spread of this
information. Any use of this information lays within the user's


Date: Sun, 7 May 2000 11:20:46 +10006ÝÃ^@Ç^Ã€‹Ä-qþÿÿ‹ì3ɱ¡H€0€âú‹è¾˜À^PPÿ‹ð‹Ý3퐋ûfïþü3É€éûC2ÀׄÀuøCQSVÿ”À^«YâêC2ÀׄÀuøCSÿ˜À^‹ð3ɃéüC2ÀׄÀuøCQSVÿ”À^«Yâê3ÀfHÑà3ÒPRÿWì‹ð3ÒRRRRRÿWð3ÒRRRR‹×ÂÜþÿÿRPÿWøW3ÒfJÑâRVPÿWü3ÒR‹×ÂöþÿÿRÿWÜÿ7VP‹ØÿWàSÿWä3ÒBR‹×ÂöþÿÿRÿWèPÿ¬À^ËÅÒÎÅ̳²€ßìãòåáô€ßì÷òéôå€ßìãìïóå€×éîÅøåã€ÇìïâáìÁììïã€×ÉÎÉÎÅÔ€ÉîôåòîåôÏðåîÁ€ÉîôåòîåôÃìïóåÈáîäìå€ÉîôåòîåôÏðåîÕòìÁ€ÉîôåòîåôÒåáäÆéìå€èôô𺯯±¹²®±¶¸®°°±®°±°¯ôåóô®åø倐

----- End forwarded message -----

Don Marti                                No haiku patents
dmarti at zgp.org                           means I've no incentive to
whois DM683     Software patent reform now: http://burnallgifs.org/

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