Advisory Details

April 14th, 2011

(Pwn2Own) WebKit WBR Tag Removal Remote Code Execution Vulnerability

ZDI-11-135
ZDI-CAN-1168

CVE ID CVE-2011-1344
CVSS SCORE 9.0, AV:N/AC:L/Au:N/C:P/I:P/A:C
AFFECTED VENDORS WebKit
AFFECTED PRODUCTS WebKit
TREND MICRO CUSTOMER PROTECTION Trend Micro TippingPoint IPS customers are protected against this vulnerability by Digital Vaccine protection filter ID ['10970']. For further product information on the TippingPoint IPS: http://www.tippingpoint.com
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.

ADDITIONAL DETAILS

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

Webkit fix:
http://trac.webkit.org/changeset/79689


DISCLOSURE TIMELINE
  • 2011-03-31 - Vulnerability reported to vendor
  • 2011-04-14 - Coordinated public release of advisory
CREDIT Vupen Security
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