Microsoft today said it will ship three security updates next week to patch 11 vulnerabilities, including the first in Office 2010 pegged "critical."
The just-released Office for Mac 2011 will also be patched for the first time on Tuesday.
Just one of the three updates was marked critical, the highest threat ranking in Microsoft's four-step system. The remaining updates were rated "important," the second-highest threat label.
Two of the trio will apply to Office, while the third will affect Forefront Unified Access Gateway 2010 , the company's VPN (virtual private networking) platform that lets enterprise workers connect with corporate applications when outside the office.
But the Office 2010 update was the one that got the attention of Andrew Storms, director of security operations at nCircle Security. "I wouldn't be a bit surprised to see 10 of the 11 [vulnerabilities] in the Office updates," said Storms.
The criticality of the Office 2010 flaw(s) surprised him. "It's the newest SKU, it has the newest file formats and the newest sandboxing," Storms said, referring to what Microsoft calls "Protected View" in the new suite.
Protected View , which has gotten a thumbs-up from security experts, isolates Word, Excel and PowerPoint files in a read-only environment that prevents malware -- which has piggybacked on Office documents for years -- from harming the PC or hijacking the system.
"Things are turned on their head this month," Storms said. "One of the bulletins is rated 'critical' for Office 2010, the newest version, but only 'important' for the older versions."
Typically, it's the other way around. Older editions of Office -- including Office XP and Office 2003 -- are prone to more flaws than newer versions, such as Office 2007 and Office 2010.
Tuesday's update for Office 2010 will be the first critical patch for the suite since it launched in May, and only the second ever for the application bundle. Microsoft patched an important vulnerability last month with the MS10-079 update.
November's patch slate is also significantly shorter than October's, when Microsoft fixed a record 49 flaws with a record 16 updates. Microsoft has taken to an even-odd security schedule, where it releases a large number of updates in even-numbered months, then follows that with fewer fixes each odd-numbered month.
Several outstanding issues that Microsoft has acknowledged in recent security advisories will go unpatched next week, according to the bare bones information the company issued today in its advance warning of the Nov. 9 fixes.
Microsoft released the newest of those advisories on Wednesday, when it confirmed that hackers are exploiting an unpatched bug in Internet Explorer (IE) using drive-by attacks.
"The good news is that there are only three security bulletins next week," Storms said. "The bad news is there's still an IE zero-day outstanding."
Other researchers agreed.
"Microsoft has published a workaround [for the IE vulnerability], but they are not expected to release an out-of-band patch, so it might be more than a month before we see a patch," said Paul Henry, a security analyst with Scottsdale, Ariz.-based Lumension. "It is interesting to note that Microsoft still doesn't believe it represents a significant threat, despite reports that it has been seen in the wild."
Both Storms and Henry pointed out that next week's updates from Microsoft aren't the only fixes that consumers and businesses face. Later today, Adobe plans to patch a Flash Player bug that the company acknowledged last week . Google also released an update for Chrome today, and Mozilla patched Firefox last week.
Microsoft will release the three security updates at approximately 1 p.m. ET on Nov. 9.