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.
The vulnerability exists due to errors in processing malformed objects contained within Excel documents. An unauthenticated, remote attacker could exploit this vulnerability by convincing a user to view a malicious file. If the user views 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
An attacker cannot exploit this vulnerability directly and instead must rely upon user interaction. The attacker must convince a user to view a malicious document, which is likely to be provided as an e-mail attachment or posted on a public website. The attacker may use social engineering to make documents more attractive to users or to convince them that the document originates from a trusted source.
Systems most at risk are end-user hosts on which users hold Administrator privileges. An exploit involving a user who holds elevated privileges could result 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 that user holds Administrator privileges, the attacker could take complete control over the system.
This vulnerability exists due to errors in processing malformed objects contained within Excel documents. An unauthenticated, remote attacker could exploit this vulnerability by convincing a user to open a malicious document using the vulnerable application. When opened, the document could cause memory corruption that could be leveraged by the attacker 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.
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.
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