ZDI-11-243: WebKit ContentEditable Inline Style Remote Code Execution Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-243

July 27, 2011

-- CVE ID:
CVE-2011-0232

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

-- Affected Vendors:
WebKit

-- Affected Products:
WebKit 

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 11099. 
For further product information on the TippingPoint IPS, visit:

    http://www.tippingpoint.com

-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of Webkit as utilized by either Apple Safari,
or Google's Chrome browser. 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 how the library handles implicitly
defined styles. When processing a specific case for a style, the
application will dispatch an event. During this dispatch, code can be
executed that can be used to manipulate the DOM tree causing a
type-switch. This type-switch can lead to code execution under the
context of the application.

-- Vendor Response:
WebKit has issued an update to correct this vulnerability. More
details can be found at:
http://support.apple.com/kb/HT4808

-- Disclosure Timeline:
2011-03-31 - Vulnerability reported to vendor
2011-07-27 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * J23 -- http://twitter.com/HansJ23

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