Browser Security Takes Center Stage This Patch Tuesday

Microsoft today issued a Security Advisory about a previously undisclosed vulnerability in Office Web Components Spreadsheet ActiveX control (OWC 10 and OWC11). The flaw is exploitable without any user interaction required, and attacks are underway.This warning came the day before Microsoft planned to patch two other 'Browse-And-Get-Owned' flaws in its July batch of patches.

From InformationWeek's Thomas Claburn's story earlier today:

"The vulnerability exists specifically in the Spreadsheet ActiveX Control and could allow an attacker who successfully exploited this vulnerability the same user rights as the local user," the Microsoft advisory states. "We are aware of limited, active attacks attempting to exploit this vulnerability."

Last week, Microsoft issued a Security Advisory about a vulnerability in its Video ActiveX Control.

In related browser security news, security researcher Robert "RSnake" Hansen, CEO of SecTheory, spotted a vulnerability that has taken some of the shine off of the security of Google Chrome. From his blog post on the flaw:

"Google Chrome appears to allow JavaScript to fire despite the fact that you are viewing source through the view-source: directive. Click here for an example (only works in Chrome with JavaScript enabled). This doesn't work in IE, Firefox, Safari, or Opera - yup, it's a Chrome only problem. Why is this a problem? Because some security people use view-source: to neuter the danger of pages that they think are potentially malicious - so that they can safely view the page without any JavaScript firing - alas, so much for that idea - at least in Chrome."

These types of flaws, both Microsoft's browse-and-get-owned and Chrome's viewing source vulnerability are important types of flaws to take note, as more attacks are increasingly setting up malicious Web sites -- as well as infecting legitimate sites -- to which they direct users for exploitation. These trends have been underway for awhile, as we noted in this post, Trusted Web Site? No So Fast.

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