TippingPoint Zero Day Initiative

Microsoft Internet Explorer Concurrent Ajax Request Memory Corruption Vulnerability

ZDI-09-037: June 10th, 2009


Affected Vendors

Affected Products

Vulnerability Details

This vulnerability allows 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.

The specific vulnerability exist due to improper AJAX request synchronization in Internet Explorer. When many asynchronous XMLHttpRequest are running concurrently memory corruption can occur that could be remotely exploited by a malicious attacker.

Vendor Response

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

Disclosure Timeline

    2009-01-15 - Vulnerability reported to vendor
    2009-06-10 - Coordinated public release of advisory


This vulnerability was discovered by: