TippingPoint Zero Day Initiative

Apple Webkit CSS Charset Text Transformation Remote Code Execution Vulnerability

ZDI-10-093: June 8th, 2010


CVSS Score

Affected Vendors

Affected Products

TippingPoint™ IPS Customer Protection

TippingPoint IPS customers are protected against this vulnerability by Digital Vaccine protection filter ID 9858. For further product information on the TippingPoint IPS:

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 Webkit's support of character sets. If the IBM1147 character set is applied to a particular element and that element has a text transformation applied to it, the application will attempt to access an object that doesn't exist in order to perform the transformation. Successful exploitation will lead to code execution under the context of the web-browser.

Vendor Response

Apple has issued an update to correct this vulnerability. More details can be found at:

Disclosure Timeline

    2010-05-03 - Vulnerability reported to vendor
    2010-06-08 - Coordinated public release of advisory


This vulnerability was discovered by:
    wushi of team509