ZDI-11-239: Apple Safari Webkit FrameOwner Element Remote Code Execution Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-239

July 27, 2011

-- CVE ID:
CVE-2011-0233

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

-- Affected Vendors:
Apple

-- Affected Products:
Apple WebKit

-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of Apple Safari Webkit. 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 the library's implementation of a
FrameOwner element. When building this tree, the application will create
a duplicate reference of an element. By freeing the referenced element,
a use-after-free condition can be made to occur which can lead to code
execution under the context of the application.

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

http://support.apple.com/kb/HT4808

-- Disclosure Timeline:
2011-01-21 - Vulnerability reported to vendor
2011-07-27 - Coordinated public release of advisory

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

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