ZDI-09-039: Microsoft Internet Explorer onreadystatechange Memory Corruption
Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-09-039
June 10, 2009

-- CVE ID:
CVE-2009-1531

-- Affected Vendors:
Microsoft

-- Affected Products:
Microsoft Internet Explorer 7

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

The specific flaw exists when repeated calls are made to
getElementsByTagName() and the reordering of the elements in the
document causes an object to be allocated. The use of the event
"onreadystatechange" during this operation improperly frees the
previously allocated resource. The combination, with repeated page
rendering, leads to the exploitable memory corruption.

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

http://www.microsoft.com/technet/security/bulletin/MS09-019.mspx

-- Disclosure Timeline:
2009-01-26 - Vulnerability reported to vendor
2009-06-10 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * ling&wushi of team509

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