ZDI-09-071: Microsoft Internet Explorer writing-mode Memory Corruption Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-09-071
October 13, 2009

-- CVE ID:
CVE-2009-2531

-- Affected Vendors:
Microsoft

-- Affected Products:
Microsoft Internet Explorer 6
Microsoft Internet Explorer 7
Microsoft Internet Explorer 8

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-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of Microsoft Internet Explorer. User
interaction is required in that a user must visit a malicious web page.

The specific flaw exists in the parsing of CSS style information. When a
writing-mode style is used with a specific combination of HTML tags,
memory corruption occurs. Exploitation of this vulnerability will lead
to remote system compromise under the credentials of the currently
logged in user.

-- Vendor Response:
Microsoft has issued an update to correct this vulnerability. More
details can be found at:

http://www.microsoft.com/technet/security/bulletin/ms09-054.mspx

-- Disclosure Timeline:
2009-06-23 - Vulnerability reported to vendor
2009-10-13 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * Sam Thomas of eshu.co.uk

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