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.
Microsoft Office Excel contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code.
This vulnerability exists due to errors in handling malformed BIFF records during the opening of Excel documents.† An unauthenticated, remote attacker could exploit this vulnerability by convincing a user to view a malicious file.† If the user opens the file, the attacker could execute arbitrary code on the system 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 2004 for Mac Office 2008 for Mac
In order to exploit this vulnerability, an attacker relies upon user participation. The attacker must convince a user to view a malicious document, likely delivered as an e-mail attachment or downloaded from a remote website. Attackers may use social engineering techniques in an attempt to convince the user that the document originates from a trusted source, possibly making users more likely to open a provided document.
If an exploit is successful, the attacker could execute arbitrary code with the privileges of the user. On systems that grant users elevated privileges, the attacker could execute code resulting in a complete system compromise. Systems such as Windows Vista or Windows 7 that contain built-in access controls, or systems that only allow users to run programs with limited privileges, are at less risk because any executed code would also run with limited privileges.
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 that user holds Administrator privileges, the attacker could take complete control over the target system.
This vulnerability exists due to errors in handling malformed BIFF records during the opening of Excel documents.† An unauthenticated, remote attacker could exploit the vulnerability by convincing a user to open a malicious document with the affected application.† The processing of malicious records within the document could trigger memory corruption that the attacker could leverage 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.
The security vulnerability applies to the following combinations of products.
2002 (XP) Base, SP1, SP2, SP3
Office for Mac
2004 Base | 2008 Base
XP (2002) Base, SP1, SP2, SP3
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