This Tuesday won’t be nearly so tame. The company plans to release 17 separate bulletins that will fix 64 specific security related software flaws, according to its April Advanced Security Bulletin Notice.

Nine of these bulletins are ranked "critical," the company’s most severe rating. These flaws can be remotely exploited, which is what makes them so troublesome. The flaws affect Microsoft Windows, Microsoft Office, Internet Explorer, Visual Studio, .NET Framework, and GDI+.

From the Microsoft Security Response Center:

This month we'll be closing some issues that Microsoft has already previously spoken to, including the SMB Browser (Critical) issue publicly disclosed Feb. 15. Microsoft assessed the situation and reported that although the vulnerability could theoretically allow Remote Code Execution, that was extremely unlikely. To this day, we have seen no evidence of attacks.

We are also planning a fix for the MHTML vulnerability in Windows, rated Important. We alerted people to this issue with Security Advisory 2501696 (including a Fix-It that fully protected customers once downloaded) back in late January. In March, we updated the advisory to let people know we were aware of limited, targeted attacks.

As always, Microsoft will host a webcast on Wednesday, April 13 where more details about the bulletins will be discussed.