Microsoft's moves against Flame may throw wrench in Patch Tuesday

The other stand-out of the seven updates slated for release next Tuesday is "Bulletin 3," said Storms, because it's marked critical and applies to all versions of Windows. "It's certainly on my list, because of its criticality and the fact that it applies to all [versions of] Windows up and down the stack," he said. "And depending on what it is, it maybe will even take the top spot."

Bulletin 1 could also be a dark horse, said Storms, who pointed out the unusual rankings Microsoft gave for some versions of Windows. For example, that update is rated "moderate" for Windows 7 RTM, or release to manufacturing -- the original 2009 version -- but critical for Windows 7 Service Pack 1 (SP1), which launched in February 2011.

The update is also rated critical for all versions of Windows Server, including 2003, 2008 and 2008 R2.

"It could be a change to Terminal Services," said Storms, referring to the service whose licensing certificate authority (CA) was exploited by hackers to generate fake Microsoft digital signatures, which were then used by Flame, a highly-advanced cyber-espionage tool.

Flame applied those stolen certificates to dupe fully-patched PCs into accepting malware disguised as legitimate updates from Microsoft's Windows Update service.

That malware is, in fact, the monkey armed with a wrench.

Yesterday, Microsoft announced that it was updating Windows Update and WSUS (Windows Server Update Service) to revamp how it signs update files.

Storms said the update to Windows Update would delay the roll-out of next week's patches by enterprises that religiously test everything before deploying to their PCs and servers. "They'll want to test the Windows Update update," said Storms of businesses. "If that breaks, everything breaks with it."

If Microsoft provides the Windows Update and WSUS updates before Tuesday, companies will spend time testing that before allowing the month's patches to reach their systems.

A smarter move for Microsoft, said Storms, would be to push the Windows Update and WSUS changes after next Tuesday, even though that would run contrary to Microsoft's promise yesterday of starting to serve the changes this week.

Microsoft will release the seven updates at approximately 1 p.m. Eastern time on June 12.

Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed . His email address is gkeizer@computerworld.com.

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