Additional technical information is available to describe the Microsoft Office Excel cache memory corruption arbitrary code execution vulnerability.
Microsoft Office Excel contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code.
This vulnerability exists due to errors when processing malformed Excel documents. An unauthenticated, remote attacker could exploit this vulnerability by convincing a user to view a malicious document. If the user opens the file, the attacker could execute arbitrary code with the privileges of the user.
Microsoft has confirmed this vulnerability in a security bulletin and released software updates.
The following Microsoft products are affected:
Office Excel 2002 SP3 and prior
Office Excel 2003 SP3 and prior
Office Excel Viewer 2003 SP3 and prior
Office 2004 for Mac and prior
Office 2008 for Mac and prior
An attacker cannot directly exploit this vulnerability, and instead must rely upon user interaction to accomplish an exploit. To successfully exploit this vulnerability the attacker must convince a user to view a malicious document using the vulnerable application. Attackers may provide documents within e-mail messages or hosted on public websites.
If an exploit is successful, the attacker could trigger the execution of arbitrary code with the privileges of the user. Systems that grant users elevated privileges may be at the greatest risk, as any code execution would also run with elevated privileges, possibly resulting in a complete system compromise.
Microsoft has released a security bulletin at the following link: MS09-067
An unauthenticated, remote attacker could exploit this vulnerability to execute arbitrary code with the privileges of the user. If the user holds elevated privileges, the attacker could execute code resulting in a complete system compromise.
This vulnerability exists due to an error when processing PivotCache streams in Excel documents. An unauthenticated, remote attacker could exploit this vulnerability by convincing a user to view an Excel file containing malicious values within a PivotCache data stream. The assignment of an attribute within objects contained within the malicious stream could trigger memory corruption. The attacker could take advantage of this memory corruption to execute arbitrary code with the privileges of the user.
Administrators are advised to apply the available software updates.
Users are advised not to open unsolicited e-mail attachments. Users should verify that attachments are safe before opening them.
Users are advised to run applications with the least privileges possible.
Users may consider applying the Microsoft Office Isolated Conversion Environment (MOICE) to safely open Excel files from suspicious or unrecognized sources on systems that are running Microsoft Office 2003 or Office 2007.
Administrators may consider using the Microsoft Baseline Security Analyzer (MBSA) scan tool to identify common security misconfigurations and missing security updates on system endpoints.
Microsoft customers can obtain updates directly by using the links in the security bulletin. These updates are also distributed by Windows automatic update features and available on the Windows Update website. Microsoft Windows Server Update Services (WSUS), Systems Management Server, and System Center Configuration Manager can assist administrators in deploying software updates.
Version 1, November 10, 2009, 1:56 PM: Microsoft Office Excel contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code with the privileges of the user. Updates are available.
XP (2002) Base, SP1, SP2, SP3 | 2003 Base, SP1, SP2, SP3, Multilingual User Interface Pack
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