Microsoft Security Advisory (911302) Revised

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Hallo dieses Security Advisory haben wir bekommen:

 

This Advisory was revised to add information regarding proof of concept code, malicious software, and a reference to Windows Live Safety Center.

 

Microsoft is investigating new public reports of a vulnerability in Microsoft Internet Explorer on Microsoft Windows 98, on Windows 98 Second Edition, on Windows Millennium Edition, on Windows 2000 Service Pack 4, on Windows XP Service Pack 1, and on Windows XP Service Pack 2. Customers who are running Windows Server 2003 and Windows Server 2003 Service Pack 1 in their default configurations, with the Enhanced Security Configuration turned on, are not affected. We have also been made aware of proof of concept code and malicious software targeting the reported vulnerability. Customers can visit Windows Live Safety Center and are encouraged to use the Complete Scan option to check for and remove this malicious software and future variants. We will continue to investigate these public reports.

 

Upon completion of this investigation, Microsoft will take the appropriate action to help protect our customers. This may include providing a security update through our monthly release process or providing an out-of-cycle security update, depending on customer needs.

This issue was originally publicly reported in May as being a stability issue that caused the browser to close. Since then, new information has been posted that indicates remote code execution could be possible. Microsoft is concerned that this new report of a vulnerability in Internet Explorer was not disclosed responsibly, potentially putting computer users at risk. We continue to encourage responsible disclosure of vulnerabilities. We believe the commonly accepted practice of reporting vulnerabilities directly to a vendor serves everyone's best interests. This practice helps to ensure that customers receive comprehensive, high-quality updates for security vulnerabilities without exposure to malicious attackers while the update is being developed.

 

Microsoft encourages users to exercise caution when they open links in e-mail. For more information about Safe Browsing, visit the Trustworthy Computing Web site.

 

We continue to encourage customers to follow our Protect Your PC guidance of enabling a firewall, applying software updates and installing antivirus software. Customers can learn more about these steps at the Protect Your PC Web site.

 

Mitigating Factors:

 

In a Web-based attack scenario, an attacker would have to host a Web site that contains a Web page that is used to exploit this vulnerability. An attacker would have no way to force users to visit a malicious Web site. Instead, an attacker would have to persuade them to visit the Web site, typically by getting them to click a link that takes them to the attacker's Web site.

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An attacker who successfully exploited this vulnerability could gain the same user rights as the local user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.

The Restricted sites zone helps reduce attacks that could try to exploit this vulnerability by preventing Active Scripting from being used when reading HTML e-mail messages. However, if a user clicks a link in an e-mail message, they could still be vulnerable to this issue through the Web-based attack scenario.

 

By default, Outlook Express 6, Outlook 2002, and Outlook 2003 open HTML e-mail messages in the Restricted sites zone. Additionally, Outlook 98, and Outlook 2000 open HTML e-mail messages in the Restricted sites zone if the Outlook E-mail Security Update has been installed. Outlook Express 5.5 Service Pack 2 opens HTML e-mail messages in the Restricted sites zone if Microsoft Security Bulletin MS04-018 has been installed.

 

By default, Internet Explorer on Windows Server 2003, on Windows Server 2003 Service Pack 1, on Windows Server 2003 with Service Pack 1 for Itanium-based Systems, and on Windows Server 2003 x64 Edition runs in a restricted mode that is known as Enhanced Security Configuration. This mode mitigates this vulnerability. See the FAQ section for this security update for more information about Internet Explorer Enhanced Security Configuration.

 

More information can be found at:

http://www.microsoft.com/technet/security/advisory/911302.mspx

 

If you have any questions regarding this alert please contact your Technical Account Manager or Application Development Consultant.

 

Thank you,

Microsoft PSS Security Team