Microsoft today delivered four security updates that patched four vulnerabilities in Windows, most of them affecting the newer editions of Vista and Windows 7.
Only one of the updates was marked "critical," Microsoft's most-serious threat ranking. Two of the remaining were labeled "important" and the fourth was tagged as "moderate."
As expected,Microsoft did not patchDuqu活动利用Windows内核漏洞。
Top on Microsoft's chart today -- and on outside researchers' to-do lists as well -- was theMS10-083update that patches a bug in Windows Vista's, Windows 7's and Server 2008's TCP/IP stack, which regulates Internet connections.
The vulnerability could be used by attackers in certain circumstances to hijack an unpatched PC, said Microsoft, which nevertheless downplayed the likelihood of successful attacks.
Ncircle Security的安全操作总监Andrew Storms说：“这个关键的错误允许通过网络进行攻击，并且乍看之下看起来很麻烦。”“但是要实现这一点看起来并不容易，因此在这种情况下，这并不像人们想象的那样大。”
Storms pointed to a post by Microsoft engineers on the安全研究与国防博客阐明了有效攻击的必要条件。
"We believe it is difficult to achieve [remote code execution] using this vulnerability considering that the type of network packets required are normally filtered at the perimeter and the small timing window ... and [that] a large number of packets are required to pull off the attack," wrote Ali Rahbar and Mark Wodrich of the Microsoft Security Response Center (MSRC).
Microsoft gave the vulnerability an exploitability index rating of "2," meaning that it expects only unreliable exploit code to appear in the next 30 days.
即便如此，一些研究人员也警告说，如果罪犯将注意力集中在虫子上，他们也许可以制定一致的利用，该漏洞可用于发动基于蠕虫的攻击。
Microsoft还更新了Vista，Windows 7和Server 2008上的Windows Mail和Windows会议空间，以修复另一个“ DLL加载劫持”漏洞。
DLL load hijacking, sometimes called "binary pre-loading," describes a class of bugs first revealed in August 2010. Microsoft has been patching its software to fix the problem -- which can be exploited by tricking an application into loading a malicious file with the same name as a required dynamic link library, or DLL -- since last November.
Today'sMS11-085update was the eighteenth Microsoft has issued to fix DLL load-hijacking vulnerabilities in its software.
"They're a dime-a-dozen these days," said Storms of the latest in the long-running series.
Researchers also noted that while Microsoft did not patch the Duqu-exploited bug, it did fix a different flaw in theTrueType font parsing engine, the component targeted by the Trojan's attacks.
MS11-084fixes a single vulnerability in the Windows kernel-mode driver "Win32k.sys" that can be exploited through a malformed TrueType font file.
"We're see a pattern of kernel-level bugs and parsing of font files," said Storms. "And they're going to have to come back and patch this again for Duqu."
Microsoft patched the TrueType engine within Win32k.sys just last month, fixing a flaw that let hackers conduct denial-of-service attacks to cripple Windows PCs. Today's bug was also categorized as a denial-of-service flaw.
代替修复程序，微软上周告诉客户，他们可以通过阻止对处理嵌入式truetype字体的动态链接库来捍卫自己的系统。
Anadvisoryoffered command-prompt strings IT administrators can use to deny access to t2embed.dll, and links to one of Microsoft's"Fix-it" tools这会自动化阻止或解密访问库的过程。
Blocking t2embed.dll, however, has side effects: Applications, including Web browsers, applications in Microsoft's Office suite and Adobe's Reader, may not render text properly.
Microsoft also updated that advisory today with a link to a list of its antivirus partners that have发行的签名to detect the kernel-based Duqu attacks.
November's security patches can be downloaded and installed via the Microsoft Update and Windows Update services, as well as through Windows Server Update Services.
Gregg Keizer涵盖了Microsoft，安全问题，Apple，Web浏览器和通用技术的计算机世界新闻。在Twitter上关注Gregg@gkeizer, onGoogle+或订阅Gregg's RSS feed。他的电子邮件地址是gkeizer@computerworld.com。
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This story, "Microsoft patches critical Windows 7 bug, downplays exploit threat" was originally published byComputerworld 。