Microsoft Tuesday released 11 security patches, six with the highest rating of "critical" that span Windows, Office, and Internet Explorer, but some say it is a combination of two non-critical vulnerabilities that should catch the eye of corporate IT.
Of the six critical vulnerabilities, none of them require any more user interaction than opening a document or visiting a malicious Web site. All six allow the attacker to take complete control of a user's machine.
The vulnerabilities affecting Internet Explorer as part of bulletin MS08-010 are troubling, according to experts, because of the wide-spread use of both IE 6 and 7, which are both at risk.
"In the past, a lot of the IE stuff has been around the scripting engines, but this is in the core HTML rendering engine," says Don Leatham, director of solutions and strategy at Lumension Security.
Office, another widely used client, is vulnerable in critically rated patches MS08-008, 009, 012 and 013.
"I would tell my mom to install 010 first, but for corporate users they should install 006 and 005 first," says Eric Schultze, CTO of Shavlik Technologies. He says MS08-005 and MS08-006, while rated important, can be viewed as critical vulnerabilities since they allow a hacker to gain control of a Web server and to escalate privileges from "user" to "admin."
"With the combination of 006 and 005, I can remotely attack your Web site and become an administrator," says Schultze. "Each one is rated 'important,' but I call them critical in both cases."
"006 is back to the days of Code Red where you can execute code on a Web server," says Schultze. "That means I can execute TFTP (Trivial File Transfer Protocol) and have TFTP come back to my machine and upload hacker tools. I can end up with a C prompt of your Web server. I can have shell access to your Web server as a user. I call that critical right away. I can install a port redirector on that system so I can attack other system in the DMZ and use the port redirector to bypass your firewalls and filtering rules."
Shultze says the final dagger comes with patch 005.
"Combine that with 005, which allows a user of a Web server to become administrator of a Web server. So I just hacked you with 006 and now as a user I can run more code to become an admin."
The last time Microsoft had as many patches rated "critical" was last May when it had seven. The last time it has more than 11 patches was February 2007 when 12 were issued.
The other five patches for February 2008 are rated important (see Microsoft's rating system) and affect Active Directory, the Windows TCP/IP stack, Internet Information Server and Office.
"There is number of concerns and with so many critical vulnerabilities it really will be on an organization-by-organization basis as far as where people start," says Jonathan Bitle, director of technical account management for Qualys. "But face it Office and Internet Explorer are two really key business tools so the fact that a number of these address Office applications and IE means those patches are probably the single largest concern for most people."
The patch releases are part of Microsoft's monthly Patch Tuesday, which falls on the second Tuesday of each month. Last week, as part of its monthly preliminary announcement, Microsoft said it had 12 patches and seven critical vulnerabilities, so clearly the company is still working to patch one other flaw.
Schultze says the preliminary announcement sent to him last week specifically mentioned the seventh critical vulnerability as a "Jscript/VBScript" issue.
Microsoft competitor Apple also released on Tuesday 11 fixes for its software, including Mac OS 10.5, Safari and Mac OS Directory Services.
In addition, the FBI is warning of a Valentine's Day Storm Worm virus.