TippingPoint Zero Day Initiative

Microsoft Internet Explorer HTTP 302 Redirect Remote Code Execution Vulnerability

ZDI-11-196: June 14th, 2011


CVSS Score

Affected Vendors

Affected Products

TippingPoint™ IPS Customer Protection

TippingPoint IPS customers are protected against this vulnerability by Digital Vaccine protection filter ID 11270. 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 HTTP 302 redirects to CDL protocols. When Internet Explorer tries to determine who is responsible for handling the protocol redirect it fails to keep a correct reference counter to a Transaction object which results in a use-after-free vulnerability. This can be leveraged into remote code execution under the context of the current user.

Vendor Response

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

Disclosure Timeline

    2011-04-04 - Vulnerability reported to vendor
    2011-06-14 - Coordinated public release of advisory


This vulnerability was discovered by:
    Peter Winter-Smith