ZDI-11-098: Apple Safari Webkit Runin Box Promotion Remote Code Execution Vulnerability

[ZDI Disclosures <zdi-disclosures@xxxxxxxxxxxxxxxx>]

ZDI-11-098: Apple Safari Webkit Runin Box Promotion Remote Code Execution 
Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-098

March 2, 2011

-- CVE ID:
CVE-2011-0132

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

-- Affected Vendors:
Apple

-- Affected Products:
Apple WebKit

-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of Apple Safari's 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 way the WebKit library implements
the requirements required for a Runin box as outlined in the Visual
Formatting Model listed in the CSS 2.1 Specification. When promoting a
run-in element the application will incorrectly free one of the child
elements of the run-in. Later, when attempting to do layout for this
element, the application will access the freed element due to the
dangling reference. This 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/HT4554

-- Disclosure Timeline:
2010-11-29 - Vulnerability reported to vendor
2011-03-02 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * wushi of team509
    * Jose A. Vazquez of {http://spa-s3c.blogspot.com/}

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