This new patch, as described in Microsoft Security Bulletin MS08-078, is designed to thwart a remote code execution exploit that can occur if a user visits a specially crafted Web page using Internet Explorer.
The patch applies to IE5.01, IE6 and all versions of IE7 running on Windows 2000 Service Pack 4, Windows XP and XP Professional, Vista, and Windows Server 2003 and 2008.
The speed of the release represents the fastest turnaround possible for such a widely deployed solution as Internet Explorer, especially given its development, testing and packaging requirements, according to Wolfgang Kandek, chief technology officer of security firm Qualys.
"Moving any faster than this would require having specific mechanisms in the base code of the application, allowing it to push out changes in a less disruptive way, and would require an extensive rewrite of Internet Explorer," Kandek said. "Other browser providers have an edge here as they already have update mechanisms included in their products."
Wednesday's rollout makes 2008 the year with the most off-cycle patches since 2006. October's interim patch release was the first in 18 months.
Microsoft's fast reaction has renewed discourse in the blogosphere and among security experts about patch scheduling. The normal rate for security rollouts, according to experts, is usually a two-week to four-month window, depending on immediacy.
The quick release in this case was not typical, according to Tyler Reguly, security engineer at nCircle Inc.
"There are people who feel that the speed at which this patch release was handled is how all patch releases are handled. I disagree with this," Reguly said. He added that "I feel that the monthly patch cycle is the right move."
There's a possible solution for those who might want a quicker response.
"If anything, Microsoft should be considering a public beta patch program," Reguly said. "I believe that this would silence many of the critics who want every patch to be handled like MS08-078."
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