It’s Patch Tuesday again, and Microsoft has plenty to keep IT admins and users busy this month. Microsoft has released ten new security bulletins for May, but the two that should get the most attention and the highest priority are both related to the Internet Explorer Web browser.

Microsoft patched a total of 33 vulnerabilities this month. There are eight patches ranked as Important, which affect a range of technologies and products including Microsoft Word, Publisher, Visio, and Lync as well as the .NET framework and the Windows kernel. The remaining two patches are both rated Critical, and both address vulnerabilities in Internet Explorer.

Marc Maiffret, CTO of BeyondTrust, explains that MS13-037 affects all supported versions of Internet Explorer—and therefore impacts all supported versions of Windows as well. He points out that three of the vulnerabilities addressed are present in all versions of Internet Explorer, and attackers will likely focus on these to target the broadest possible pool of vulnerable systems with the least amount of effort.

MS13-037 is the expected, or planned, update for Internet Explorer. MS13-038, on the other hand, is a rushed, last-minute addition to the Patch Tuesday inventory. It was less than two weeks ago that a zero day flaw was discovered in IE8.

Andrew Storms, director of security operations for nCircle (a Tripwire company), says, “As anticipated, Microsoft released a critical update for Internet Explorer 8 today that patches an outstanding zero-day bug reportedly used in a targeted watering hole attack against the US Department of Labor. Speculation earlier this week suggests the same attack also targeted employees at USAID and Department of Energy.”

To read this article in full or to leave a comment, please click here