ZDI-10-152: Apple WebKit RTL LineBox Overflow Remote Code Execution Vulnerability
http://www.zerodayinitiative.com/advisories/ZDI-10-152 
August 11, 2010

-- CVE ID:
CVE-2010-0049

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

-- Affected Vendors:
Apple

-- Affected Products:
Apple WebKit

-- Vulnerability Details:
This vulnerability allows remote attackers to execute arbitrary code on
vulnerable installations of Apple'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 due to the method by which the Webkit library
renders right-to-left text. If a linebox has a width greater than it's
container, Webkit frees an object that upon page destruction is freed
again. An attacker can exploit this to code execute remote code under
the context of the application.

-- Vendor Response:
Apple states:
this issue was fixed in Safari 4.0.5, and iOS 4 for iPhone and iPod
touch iOS 3.2
iOS 4: http://support.apple.com/kb/HT4225 
Safari 4.0.5: http://support.apple.com/kb/HT4070 

-- Disclosure Timeline:
2010-02-18 - Vulnerability reported to vendor
2010-08-11 - Coordinated public release of advisory

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

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