ZDI-10-152: Apple WebKit RTL LineBox Overflow Remote Code Execution Vulnerability

Type securityvulns
Reporter Securityvulns
Modified 2010-08-14T00:00:00


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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