ZDI-09-033: Apple WebKit dir Attribute Freeing Dangling Object Pointer Vulnerability

ZDI-09-033: Apple WebKit dir Attribute Freeing Dangling Object Pointer
Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-09-033
June 8, 2009

– CVE ID:
CVE-2009-1701

– Affected Vendors:
Apple

– Affected Products:
Apple Safari

– Vulnerability Details:
This vulnerability allows attackers to execute arbitrary code on
vulnerable software utilizing the Apple WebKit library. User interaction
is required to exploit this vulnerability in that the target must visit
a malicious page.

The specific flaw exists when the document.body element contains a
specific XML container containing various elements supporting the 'dir'
attribute. During the destruction of this element, if the rendering
object responsible for the element is being removed, the application
will then make a call to a method for an object that doesn't exist which
can lead to code execution under the context of the current user.

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

http://support.apple.com/kb/HT3613

– Disclosure Timeline:
2009-02-09 - Vulnerability reported to vendor
2009-06-08 - Coordinated public release of advisory

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

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