ZDI-11-198: (Pwn2Own) Microsoft Internet Explorer Uninitialized Variable Information Leak Vulnerability

ZDI-11-198: (Pwn2Own) Microsoft Internet Explorer Uninitialized Variable Information Leak
Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-198

June 14, 2011

– CVSS:
7.5, (AV:N/AC:L/Au:N/C:P/I:P/A:P)

– Affected Vendors:
Microsoft

– Affected Products:
Microsoft Internet Explorer

– TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 11255.
For further product information on the TippingPoint IPS, visit:

http://www.tippingpoint.com

– Vulnerability Details:
This vulnerability allows remote attackers to leak information on
vulnerable installations of Internet Explorer. User interaction is
required to exploit this vulnerability in that the target must visit a
malicious page or open a malicious file.

The specific flaw exists within Internet Explorer that allows malicious
users to leak information about the memory layout of an Internet
Explorer process. When creating a new 'Option' HTML Element, the 'index'
field of the object is not set to zero and can be used to leak the
location of the global variable table. This can be used to defeat ASLR
or to remove the need for heap spraying while exploiting a remote code
execution flaw.

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

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

– Disclosure Timeline:
2011-03-09 - Vulnerability reported to vendor
2011-06-14 - Coordinated public release of advisory

– Credit:
This vulnerability was discovered by:
* Stephen Fewer of Harmony Security (www.harmonysecurity.com)

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