Update to Alleged Information and Security Issue with Mouse Position Behavior

December 14th, 2012

Over the last few days we’ve seen reports alleging abuse of a browser behavior regarding mouse position. Microsoft is working closely with other companies to address the concern of mouse position movement. From what we know now, the underlying issue has more to do with competition between analytics companies than consumer safety or privacy.

We are actively working to adjust this behavior in IE. There are similar capabilities available in other browsers. Analytics firms can expect to do viewpoint detection in IE similarly to how they do this in other browsers. We will update this blog with more information as it is available.

Online advertisers started a shift (link) “from a ‘served’ to a ‘viewable’ impression[s].” Many different analytics companies stepped up to compete in this space. That competition has had many public results, including lawsuits (link). One of the companies involved in this space is, which recently reported an issue in IE involving mouse pointer information. is an advertising analytics company. Their recent blog post, “There are two ways to measure ad viewability. There is only one right way,” makes their point of view very clear. Different analytics companies use different and equivalent methods to gather consumer information across different browsers on different devices.

The only reported active use of this behavior involves competitors to providing analytics. The theoretical use of this behavior to compromise the safety or privacy of consumers is something Microsoft’s security team has discussed with researchers across the industry. We take these risks very seriously. Getting all the pieces to line up in order to take advantage of this behavior – serving an ad to a site that asks for a logon, the user using an on screen (or virtual) keyboard, knowing how that onscreen keyboard works – is hard to imagine. From investigating the specific behavior when mouse position data is visible outside the browser window, sites can view only the mouse state; they cannot view the actual content that the user is interacting with. From our conversations with security researchers across the industry, we see very little risk to consumers at this time. As we have stated previously, there are no reported cases of any consumer having their information compromised.  

—Dean Hachamovitch, Corporate Vice President, Internet Explorer

Since the time of our post – these additional security blogs provide a good and balanced overview with respect to this topic: Actionable Intelligence: The Mouse That Squeaked and Warns of Massive IE Security Flaw; But is it Legit?