ZDI-11-135: (Pwn2Own) WebKit WBR Tag Removal Remote Code Execution Vulnerability

Type securityvulns
Reporter Securityvulns
Modified 2011-04-19T00:00:00


ZDI-11-135: (Pwn2Own) WebKit WBR Tag Removal Remote Code Execution Vulnerability


April 14, 2011

-- CVE ID: CVE-2011-1344

-- CVSS: 9, (AV:N/AC:L/Au:N/C:P/I:P/A:C)

-- Affected Vendors: WebKit

-- Affected Products: WebKit WebKit

-- TippingPoint(TM) IPS Customer Protection: TippingPoint IPS customers have been protected against this vulnerability by Digital Vaccine protection filter ID 10970. For further product information on the TippingPoint IPS, visit:


-- Vulnerability Details: This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of 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 way the Webkit library handles WBR tags on a webpage. By adding children to a WBR tag and then consequently removing the tag through, for example, a 'removeChild' call it is possible to create a dangling pointer that can result in remote code execution under the context of the current user.

-- Vendor Response: Google patch on March 12, 2011: http://googlechromereleases.blogspot.com/2011/03/stable-and-beta-channel-updates.html

Apple patch on April 14, 2011: http://support.apple.com/kb/HT4606 http://support.apple.com/kb/HT4607 http://support.apple.com/kb/HT4596

-- Disclosure Timeline: 2011-03-31 - Vulnerability reported to vendor 2011-04-14 - Coordinated public release of advisory

-- Credit: This vulnerability was discovered by: * Vupen Security

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