Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE-----
===========================================================================
AUSCERT External Security Bulletin Redistribution
ESB-2001.218 -- Microsoft Security Bulletin MS00-079 (version 2.0)
HyperTerminal Buffer Overflow Vulnerability
29 May 2001
===========================================================================
AusCERT Security Bulletin Summary
---------------------------------
Product: HyperTerminal
Vendor: Microsoft
Operating System: Windows 98
Windows 98SE
Windows Me
Windows NT 4.0
Windows 2000
Impact: Execute Arbitrary Code/Commands
Access Required: Remote
Ref: ESB-2000.300
- --------------------------BEGIN INCLUDED TEXT--------------------
- ----------------------------------------------------------------------
- -
Title: HyperTerminal Buffer Overflow Vulnerability
Released: 18 October 2000
Revised: 24 May 2001 (version 2.0)
Software: HyperTerminal on Windows 98, 98SE, Windows ME,
Windows NT 4.0, Windows 2000
Impact: Privilege Elevation
Bulletin: MS00-079
Microsoft encourages customers to review the Security Bulletin at:
http://www.microsoft.com/technet/security/bulletin/MS00-079.asp.
- ----------------------------------------------------------------------
- -
Reason for Revision:
====================
Microsoft has re-released this bulletin to inform customers of the
availability of an updated set of patches to address both the
original and a second vulnerability identified in HyperTerminal.
Information about the second issue is discussed in the Issue section
below and in the security bulletin referenced above.
Issue:
======
The HyperTerminal application is a communications utility that
installs by default on all versions of Windows 98, 98SE, Windows ME,
Windows NT 4.0, and Windows 2000. The product contains two unchecked
buffers through which an attacker could potentially cause code of her
choice to run on another user's machine:
- One resides in a section of the code that processes Telnet URLs.
If a user opened an HTML mail that contained a particular type of
malformed Telnet URL, and HyperTerminal were configured as the
default Telnet client, it would trigger the buffer overrun.
HyperTerminal is the default Telnet client on Windows 98, 98SE and
ME. It is not the default Telnet client on Windows 2000.
- The other resides in a section of the code that processes session
files - files that enable HyperTerminal users to specify session
parameters such as the connection method and the destination host. If
a user opened a session file that contained a particular type of
malformed information, it would trigger the buffer overrun.
Although HyperTerminal ships as part of several Microsoft products,
it was developed by a third party. Additional information on the
vulnerability and a patch for their full version product,
HyperTerminal Private Edition, is available from their web site at
www.hilgraeve.com
Mitigating Factors:
====================
The malicious user must entice another user into clicking on a
specially-formed telnet URL or opening a malformed HyperTerminal
session file.
Patch Availability:
===================
- A patch is available to fix this vulnerability. Please read the
Security Bulletin
http://www.microsoft.com/technet/security/bulletin/ms00-079.asp
for information on obtaining this patch.
Acknowledgment:
===============
- Luciano Martins of USSR Labs (www.ussrback.com)
- ----------------------------------------------------------------------
THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED
"AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL
WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY
DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL,
CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF
MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION
OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO
THE FOREGOING LIMITATION MAY NOT APPLY.
- --------------------------END INCLUDED TEXT--------------------
You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to auscert@auscert.org.au
and we will forward your request to the appropriate person.
This security bulletin is provided as a service to AusCERT's members. As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content. The decision to use any or all of this information is
the responsibility of each user or organisation, and should be done so in
accordance with site policies and procedures.
NOTE: This is only the original release of the security bulletin. It may
not be updated when updates to the original are made. If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the original authors to ensure that the information is still current.
Contact information for the authors of the original document is included
in the Security Bulletin above. If you have any questions or need further
information, please contact them directly.
Previous advisories and external security bulletins can be retrieved from:
http://www.auscert.org.au/Information/advisories.html
If you believe that your system has been compromised, contact AusCERT or
your representative in FIRST (Forum of Incident Response and Security
Teams).
Internet Email: auscert@auscert.org.au
Facsimile: (07) 3365 7031
Telephone: (07) 3365 4417 (International: +61 7 3365 4417)
AusCERT personnel answer during Queensland business hours
which are GMT+10:00 (AEST).
On call after hours for emergencies.
-----BEGIN PGP SIGNATURE-----
Version: 2.6.3i
Charset: noconv
Comment: ftp://ftp.auscert.org.au/pub/auscert/AUSCERT_PGP.key
iQCVAwUBOxN+wyh9+71yA2DNAQHiNwP+Kb1G0E4uE52YhCe/KsrGbaI1jStb93K9
ePX8HA51VqBlgadgDTwohhpKLiANK5mvGsUq/rR7eAdqRCAjPrr/xIDTV73XXmNI
KFS9//9WB8UEK6+Mwu+mjZFhlo189o9lfdMEfWDO4ptCbA5i/k9FOoHbLAQgoZwm
8qmuqgMcbA8=
=h4zs
-----END PGP SIGNATURE-----