Microsoft Office contains a vulnerability that could allow an unauthenticated, remote attacker to access sensitive information on a targeted system. Updates are available.
A vulnerability in the Word component of Microsoft Office could allow an unauthenticated, remote attacker to access sensitive information.
The vulnerability is due to improper handling of external XML entities by the affected software when the entity is resolved in other external XML entity declarations. An attacker could exploit the vulnerability by providing a crafted file designed to submit malicious input to the affected software and persuading a user to open the file or follow a crafted link. A successful exploit could allow the attacker to access sensitive information. The attacker could use the information to launch additional attacks.
Microsoft has confirmed the vulnerability in a security bulletin and released software updates.
The following Microsoft products are affected:
Microsoft Office 2003 SP3
Microsoft Word 2007 SP3
Microsoft Word Viewer
To exploit the vulnerability, the attacker may provide a link that directs a user to a malicious site or provide a crafted file intended to submit malicious input to the affected software. The attacker may use misleading language or instructions to persuade the user to follow the provided link or open the provided file.
Microsoft has corrected the vulnerability by modifying the way that Word resolves external entities in XML files.
Microsoft has released a security bulletin at the following link: MS13-072
An unauthenticated, remote attacker could exploit the vulnerability to access sensitive information on a targeted system. The attacker could use the information to launch additional attacks.
The vulnerability is due to improper handling of external XML entities by the affected software when the entity is resolved in other external XML entity declarations.
An unauthenticated, remote attacker could exploit the vulnerability by providing a crafted file, designed to submit malicious input to the affected software, to a user via email, chat, or a link, and persuading the user to open the file or follow the crafted link. When the affected software processes the file, how the external XML entity is resolved by the affected software could allow read access to files on the targeted system. A successful exploit could allow the attacker to access sensitive information. The attacker could use the information to launch additional attacks.
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.
Users are advised not to open email messages from suspicious or unrecognized sources. If users cannot verify that links or attachments included in email 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.
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