Microsoft IE Zero-Day Flaw Exposure Widens
There is still no official patch from Microsoft as weaponized exploits for Internet Explorer begin to appear, but there is a simple step that enterprise users can take to mitigate the risk.Two weeks ago, Microsoft first warned its users that it was investigating public reports about a zero-day vulnerability in its Internet Explorer (IE) Web browser. It's a vulnerability that still has not been patched in a full update and is now actively being exploited by attackers. In response to an inquiry from eWEEK about the issue, Microsoft declined to provide any specific timing about when a full patch for the issue, now known as CVE-2013-3893, would be available. "We are aware of a limited number of targeted attacks; customers who have installed the Fix It are not at risk from this issue," a Microsoft spokesperson said. "We encourage customers who have not applied the Fix It provided by Security Advisory 2887505 to do so to help ensure they are protected as we continue work on a security update." The Fix It is a "Band-Aid" approach to the security issue, providing a fix for users who physically visit the Fix It site and click the Fix It button. A full patch, in contrast, is made available to all Microsoft users through the Windows Update mechanism that all Windows users have access to and many users have set for fully automated patching.
Ken Pickering, director of engineering at CORE Security, told eWEEK that there are already at least four advanced persistent threats (APTs) known to be using the CVE-2013-3893 attack as part of their spearphishing campaigns on prospective targets. Spearphishing is a form of targeted fake email (phishing) attack. The fact that the vulnerability is being actively exploited should merit an emergency response from Microsoft, Pickering added.