"Certainly for bulletin count, it looks like a pretty flat line to me," said Storms, using the term "bulletin" -- Microsoft's label -- to describe security updates. "This year, it looks like the up and down pattern has ended."

Wolfgang Kandek, CTO of Qualys, agreed with Storms.

"In prior years we have seen much stronger differences [in the number of updates each month], ranging from 2 to 17," Kandek said in an email. "We are not sure this [flattening] is intended, but it makes the workload much more predictable and is preferable to the more bursty release mode."

Of the seven updates, Microsoft tagged three as "critical," the highest threat ranking in its four-step system, and the other four as "important," the next-most serious score.

Four updates will address vulnerabilities in Windows; four will impact Office, Microsoft's popular application suite; and one will affect the Silverlight development framework. That count exceeds seven because one of updates tackles bugs in all three of those lines.