Microsoft has dismissed allegations that Internet Explorer can allow attackers to track the position of the user's mouse cursor, arguing that the original report was self-serving and that the observed behavior does not represent a credible threat.
"From what we know now, the underlying issue has more to do with competition between analytics companies than consumer safety or privacy," Dean Hachamovitch, corporate VP of Microsoft's Internet Explorer group, said in a blog post.
The company said the alleged vulnerability is present in IE versions 6 through 10, and that although it had disclosed the threat privately to the Microsoft Security Research Center, Redmond had said it had "no immediate plans" to issue a patch.
"The vulnerability is already being exploited by at least two display ad analytics companies across billions of page impressions per month," Spider.io said.
But on Thursday, Hachamovitch argued that Spider.io was only concerned about what these web analytics companies were allegedly doing because Spider.io is itself a web analytics company, and that its complaints, purportedly on behalf of users, were really motivated by commercial concerns.
"The only reported active use of this behavior involves competitors to Spider.io providing analytics," Hachamovitch wrote.
In its initial report, Spider.io claimed that by recording the movement of a user's mouse cursor on the screen, attackers could potentially monitor what users type into onscreen keyboards and virtual keypads, allowing them to record passwords and other sensitive data.
Unlikely, Hachamovitch said.
"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," he wrote. "From our conversations with security researchers across the industry, we see very little risk to consumers at this time."
In a separate blog post on Friday, Spider.io said, "We do not feel at all comfortable participating in this public debate." But they went ahead anyway.
"According to existing privacy standards, it is not ok for a browser to leak your mouse co-ordinates outside of the particular browser window," company reps wrote. "Should Microsoft fix this bug? This is a matter for the public to decide – in particular, it's a matter for the privacy experts."
Curiously enough, however, the second paragraph of Hachamovitch's blog post begins with a rather germane sentence: "We are actively working to adjust this behavior in IE." ®