TippingPoint Zero Day Initiative
 

Webkit fontface Invalid Font Family Remote Code Execution Vulnerability

ZDI-12-054: March 26th, 2012

CVE ID

CVSS Score

Affected Vendors

Affected Products

    WebKit

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 parsing and utilization of font objects. When the code parses the @font-face CSS element it does not validate that the font-family is legitimate. Later, if the same font-family is applied within CSS the code will access an invalid element of its internal font object. This can be leveraged by a remote attacker to execute code under the context of the user running the browser.

Vendor Response

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

Disclosure Timeline

    2011-07-06 - Vulnerability reported to vendor
    2012-03-26 - Coordinated public release of advisory

Credit

This vulnerability was discovered by:
    wushi of team509
    miaubiz