NGSSoftware Insight Security Research Advisory

Name: MSN Heartbeat Control Buffer Overflow
Systems Affected: Microsoft Internet Explorer with the MSN Heartbeat Control
Severity: High
Vendor URL: http://zone.msn.com/
Author: John Heasman [ john@ngssoftware.com ]
Date of Public Advisory: 19th January 2004
Advisory number: #NISR19012005d
Advisory URL: http://www.ngssoftware.com/advisories/heartbeatfull.txt
Reference: http://www.ngssoftware.com/advisories/heartbeat.txt


Description
***********

A vulnerability has been discovered in the MSN Heartbeat ActiveX component
which can allow remote code execution through Internet Explorer.

This component is installed by some MSN gaming sites and is marked safe
for scripting by default.


Details
*******

When initialising the Heartbeat control in a webpage, there are several
parameters which must be set to access the functionality within the
control, such as urls and filenames. When providing an overly string for
the SetupData parameter, a heap based buffer overflow occurs. A reliable
arbitrary dword overwrite is possible, and it is trivial to exploit this
flaw.


Fix Information
***************

Microsoft have released an update for the MSN Heartbeat component which
addresses this issue.

This can be downloaded from:

http://www.microsoft.com/technet/security/bulletin/MS04-038.mspx

A check for this vulnerability has been added to Typhon III, NGSSoftware's
advanced vulnerability assessment scanner. For more information please
visit the NGSSoftware website at http://www.ngssoftware.com/


About NGSSoftware
*****************

NGSSoftware design, research and develop intelligent, advanced application
security assessment scanners. Based in the United Kingdom, NGSSoftware
have offices in the South of London and the East Coast of Scotland.
NGSSoftware's sister company NGSConsulting, offers best of breed security
consulting services, specialising in application, host and network
security assessments.

http://www.ngssoftware.com/

Telephone +44 208 401 0070
Fax +44 208 401 0076

enquiries@ngssoftware.com