ZDI-11-095: Apple Webkit Error Message Mutation Remote Code Execution Vulnerability

ZDI-11-095: Apple Webkit Error Message Mutation Remote Code Execution
Vulnerability

http://www.zerodayinitiative.com/advisories/ZDI-11-095

March 2, 2011

– CVE ID:
CVE-2010-1824

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

– Affected Vendors:
Apple

– Affected Products:
Apple WebKit

– TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 10890.
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 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 methodology the application takes to
inform a user about an error while parsing a malformed document. When
displaying the error message, the application will append the message to
the current instance of the DOM tree causing another element to be
removed which will lead to the styles being recalculated. When the
styles are recalculated the application will access the initially freed
element 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/HT4554

– Disclosure Timeline:
2010-10-18 - Vulnerability reported to vendor
2011-03-02 - Coordinated public release of advisory

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

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