NSFOCUS Security Advisory(SA2011-01)

Microsoft Internet Explorer Link Property Processing Memory Corruption Vulnerability

Release Date: 2011-06-15

CVE ID: CVE-2011-1250

http://www.nsfocus.com/en/advisories/1101.html

Affected Software and System:
=============================

Microsoft Internet Explorer 6
Microsoft Internet Explorer 7
Microsoft Internet Explorer 8

Impact:
======

NSFOCUS Security Team discovered a security vulnerability in Microsoft
Internet Explorer. This flaw could be used to corrupt memory resulting in
application crash and possible code execution by convincing users to open
specially crafted HTML files.


Description:
============

Microsoft Internet Explorer is the most popular Web browser application.

It was found that unexpected objects access could be triggered in the way
of IE processing malformed Link object property, directly resulted in
unauthorized memory access and possible IE process crash or code
execution. Attackers can execute malicious code in the context of
vulnerable system by convincing users to visit webpages containing
malicious code, and thus take control of user system. This flaw exists
in Web browser itself without triggering additional ActiveX controls.

Workaround:
===========

Users for Windows can mitigate the impact from the flaw before install
relative patches according to the following steps:

* Temporarily use other non-IE kernel browsers like Chrome, Firefox and
  Opera.

* Make use of Microsoft EMET that could greatly prevent utility of
  vulnerability but can not stop its triggering.

  It is available from the following link:
  http://go.microsoft.com/fwlink/?LinkID=200220&clcid=0x409 

Vendor Status:
==============
 
The vulnerability has been fixed in Microsoft Security Bulletin MS11-050.
For details, please refer to the following link:

http://www.microsoft.com/technet/security/bulletin/MS11-050.mspx


Additional Information:
==================

The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2011-1250 to this issue. This is a candidate for inclusion in
the CVE list (http://cve.mitre.org), which standardizes names for
security problems. Candidates may change significantly before they
become official CVE entries.

Credit:
======

This vulnerability was discovered by Wang Liejun of NSFOCUS Security Team.

DISCLAIMS:
==========

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(c) 2011 NSFOCUS.
-- 
Regards,

NSFOCUS Security Team <security@nsfocus.com>
NSFOCUS Information Technology Co.,Ltd. (http://www.nsfocus.com)

PGP Key fingerprint = F8F2 F5D1 EF74 E08C 02FE 1B90 D7BF 7877 C6A6 F6DA