ZDI-09-034: Apple Safari SVG Set.targetElement() Memory Corruption
Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-09-034
June 8, 2009

-- CVE ID:
CVE-2009-1709

-- Affected Vendors:
Apple

-- Affected Products:
Apple Safari

-- TippingPoint(TM) IPS Customer Protection:
TippingPoint IPS customers have been protected against this
vulnerability by Digital Vaccine protection filter ID 6569.
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. User interaction is required
to exploit this vulnerability in that the target must visit a malicious
page.

The specific flaw exists in the garbage collection of JavaScript set
elements in WebCore. When an SVG set object is appended to an SVG marker
element that is dereferenced, calls to the targetElement attribute will
fail to reference count the marker element. When the set element is
appended to another object, subsequent calls to the targetElement
attribute will result in a heap corruption which can be leveraged to
execute arbitrary code 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:
2008-11-10 - Vulnerability reported to vendor
2009-06-08 - Coordinated public release of advisory

-- Credit:
This vulnerability was discovered by:
    * Anonymous

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