Microsoft said it would deliver 11 security updates next week to patch 25 vulnerabilities in Windows, Office and Exchange.
"Big day next Tuesday," said Andrew Storms, director of security operations at nCircle Network Security, of the patch news.
In its monthly advance notification, Microsoft spelled out next week's double-digit Patch Tuesday, which is entirely in line with company's pattern of alternating large- and small-sized updates, said Storms. "This fits with what we expected," he said, "a double-digit bulletin [Patch Tuesday] and double-digit CVEs."
The latter, for Common Vulnerabilities and Exposures, is the identifying number each individual vulnerability receives when it's logged into the public CVE database. "We get this up-and-down from Microsoft now."
Last month, Microsoft issued only two updates that patched six vulnerabilities; February's security fixes came in 13 bulletins that fixed 26 flaws.
"The good news is that Microsoft is fixing two outstanding bugs," Storms continued.
Storms was referring to news from Jerry Bryant, a group manager with the Microsoft Security Response Center (MSRC), who said that among the 11 updates would be two that patch previously-acknowledged vulnerabilities. Microsoft disclosed the bugs in November 2009 and March 2010.
The March security advisory warned Windows XP users not to press the F1 key when prompted by a website, Microsoft's response to a report by Polish security researcher Maurycy Prodeus of a vulnerability in VBScript that attackers could exploit to hijack PCs running Internet Explorer (IE).
The November 2009 warning was prompted by reports of a bug in SMB (Server Message Block), a Microsoft-made network file- and print-sharing protocol, within Windows 7 and Windows Server 2008 R2, Microsoft's newest operating systems. At the time, the flaw was the first Microsoft-confirmed zero-day vulnerability for Windows 7.
"That's a little long...for the SMB bug," said Storms, talking about the five-month stretch between Microsoft acknowledging the vulnerability and fixing it. "I'd say that it's more than likely that it affected more [code] than they expected, or they just didn't see a lot of need for a patch, considering the threat landscape."
Of the 11 updates, those Microsoft today marked as "Bulletin 1" and "Bulletin 2" were the most interesting to Storms because both were marked "critical," and both affected all supported versions of Windows -- from Windows 2000 to Windows 7 and Windows Server 2008 R2.
Five of the impending updates were tagged critical by Microsoft, the top threat ranking in its four-step scoring system. Another five were labelled "Important," the second-highest next rating, while the last was marked "Moderate."
Windows 7 will receive four of the 11 updates, including the one designed to patch the VBScript-F1 vulnerability, even though Microsoft previously said that the bug did not impact the new OS.
"Severity ratings do not apply to this update because the vulnerability discussed in this bulletin does not affect this software," Microsoft said in today's alert, speaking of Vista, Server 2008, Windows 7 and Server 2008 R2. "However, Microsoft recommends that customers of this software apply this security update as a defence-in-depth measure."
Also on the slate: Patches for Publisher, the desktop publishing program included with some editions of Microsoft Office, and for Exchange, the widely-used e-mail server.
"It gets messier around deployment when Exchange has to be patched," said Storms. "Administrators have to balance uptime [for the mail server] with the risk. This probably needs to be patched as soon as possible, but companies should ask themselves: 'What's the risk of downtime?'"
Microsoft will not patch a vulnerability in IE confirmed by the company in early February. Hackers can use the bug to attack IE on Windows XP, or IE7 or IE8 on other versions of Windows if the browser's Protected Mode has been disabled, Microsoft said then.
Bryant, of the MSRC, again reminded users that several editions of Windows are nearing forced support retirement, including Vista RTM next Tuesday, and Windows XP SP2 and Windows 2000 - the latter two staring at a 13 July deadline.
Microsoft will release the two updates at approximately 1pm ET on April 13.