TippingPoint Zero Day Initiative

Microsoft Internet Explorer Layout Remote Code Execution Vulnerability

ZDI-13-007: February 1st, 2013


CVSS Score

Affected Vendors

Affected Products

TippingPoint™ IPS Customer Protection

TippingPoint IPS customers are protected against this vulnerability by Digital Vaccine protection filter ID 12584. For further product information on the TippingPoint IPS:

Vulnerability Details

This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Microsoft Internet Explorer. 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 Internet Explorer handles CCaret objects. After the CCaret object has been freed there exists a race condition to reclaim the target objects heap buffer before a background thread issues a message to update the screen caret and reuse the stale pointer. An attacker can leverage this vulnerability to execute code under the context of the current process.

Vendor Response

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

Disclosure Timeline

    2012-11-09 - Vulnerability reported to vendor
    2013-02-01 - Coordinated public release of advisory


This vulnerability was discovered by:
    Stephen Fewer of Harmony Security (www.harmonysecurity.com)