ZDI-10-142: Apple Webkit SVG First-Letter Style Remote Code Execution Vulnerability

ZDI-10-142: Apple Webkit SVG First-Letter Style Remote Code Execution Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-10-142
August 5, 2010

– CVE ID:
CVE-2010-1785

– CVSS:
10, (AV:N/AC:L/Au:N/C:C/I:C/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 10065.
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 library's implementation of the
first-letter style in the context of an SVG text element. Upon applying
the style to this element, the library will calculate the height for
determining the overflow for an inline box. While traversing the
elements for the height, the library will utilize data from a
non-existent linebox. Successful exploitation will 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/HT4276

– Disclosure Timeline:
2010-06-01 - Vulnerability reported to vendor
2010-08-05 - Coordinated public release of advisory

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

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