Microsoft Office contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code on a targeted system. Updates are available.
A vulnerability in Microsoft Office could allow an unauthenticated, remote attacker execute arbitrary code.
The vulnerability is due to improper memory operations performed by the Portable Network Graphics (PNG) processing component of the affected software. An attacker could exploit the vulnerability by persuading a user to open a malicious file or follow a malicious link. A successful exploit could allow the attacker to execute arbitrary code with the privileges of the user. If the user holds elevated privileges, the attacker could completely compromise the system.
Microsoft has confirmed the vulnerability in a security bulletin and released software updates.
The following Microsoft products are affected:
Microsoft Office 2003 SP3
Microsoft Office for Mac 2011
To exploit the vulnerability, the attacker may provide a link that directs a user to a malicious site or persuade a user to open a malicious file intended to submit malicious input to the affected software.
Microsoft has resolved the vulnerability by correcting the way that Microsoft Office parses crafted files.
Microsoft has released a security bulletin at the following link: MS13-051
An unauthenticated, remote attacker could exploit the vulnerability to execute arbitrary code with the privileges of the user. If the user holds elevated privileges, the attacker could completely compromise the targeted system.
The vulnerability is due to improper memory allocation operations performed by the PNG processing component of the affected software when handling crafted Office files.
An unauthenticated, remote attacker could exploit the vulnerability by persuading a user to open a crafted file or follow a crafted link. When the malicious file is processed by the affected software, a memory corruption error may occur that the attacker could use to execute arbitrary code. A successful exploit could allow the attacker to execute arbitrary code with the privileges of the user. If the user holds elevated privileges, the attacker could achieve a complete compromise of targeted system.
Administrators are advised to apply the appropriate updates.
Administrators are advised to allow only trusted users to have network access.
Administrators may consider using the Microsoft Baseline Security Analyzer (MBSA) scan tool to identify common security misconfigurations and missing security updates on system endpoints.
Administrators of Office for Mac 2011 may consider dissociating Office binary file formats from Office in the LaunchServices database. The file formats to dissociate are the following: .doc, .dot, .docm, .dotm, .ppt, .pot, .pps, .pptm, .potm, .ppsm, .xls, .xlt, .xlsb, .xlsm, and .xltm.
Users are advised not to open e-mail messages from suspicious or unrecognized sources. If users cannot verify that links or attachments included in e-mail messages are safe, they are advised not to open them.
Users are advised not to visit websites or follow links that have suspicious characteristics or cannot be verified as safe.
Administrators are advised to use an unprivileged account when browsing the Internet.
Administrators are advised to monitor critical systems.
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 Microsoft Update service. 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.
Office for Mac
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