It's Patch Tuesday--the sixth one of 2013. As far as Patch Tuesdays go, June is relatively light--with a mere five security bulletins, and only one rated as Critical--but that's no reason to let your guard down.
The average number of security bulletins for the first five months of 2013 was nine. A paltry five security bulletins for June is only about half what IT admins have come to expect, so it's nice to get to take it easy a bit. The one Critical security bulletin is the cumulative update for Internet Explorer, along with four Important security bulletins that still deserve prompt attention.
Lamar Bailey, director of security research for Tripwire, acknowledges that monthly Internet Explorer updates have become the norm. Bailey points out that it's still a bit unusual for a single IE update to address 19 separate vulnerabilities, and proclaims, "It's just a matter of time before one of these gets exploited."
Qualys CTO Wolfgang Kandek agrees. Kandek stresses in a blog post that the flaws in MS13-047 affect all supported versions of Internet Explorer from IE6 to IE10, running on all supported versions of Windows from XP to RT. "Given the large number of vulnerabilities fixed, this will be the main target for attackers to reverse engineer and construct an exploit that can be delivered through a malicious webpage."
Most security experts agree that MS13-047 should be your highest priority, and that the update should be applied as soon as possible.
There are some who believe that MS13-050 is more urgent, though. Ross Barrett, senior manager of security engineering at Rapid7, believes that the top priority should be MS13-051--a security bulletin that addresses vulnerabilities in Office 2003 and Office 2011 for Mac.
According to Barrett, "This issue is seeing limited, targeted exploitation in the wild and the only reason Microsoft hasn't tagged it as a "Critical" issue is based on the limited number of affected platforms." Barrett also stresses that exploitation of this issue requires the user to interact with a malicious document.
Tyler Reguly, technical manager of security research for Tripwire, laments, "It's disappointing to see that Mac users of Microsoft software get the short end of the stick when it comes to security. You have to wonder how a vulnerability that only affects Office 2003 is also in Office for Mac 2011," adding, "As a Mac user, I find this advisory very disconcerting."
Adobe also joins the party today with the release of a new version of Flash. The update addresses a vulnerability discovered by the Google security team. Users of Chrome and Internet Explorer 10 will receive the update automatically as a function of updates for their browsers.
As always, all five of the Microsoft security bulletins, as well as the update from Adobe, should be reviewed, and you should determine the priority relative to the products and services in use on your systems, and the possible exposure to exploit.