Microsoft Silverlight contains a vulnerability that could allow an unauthenticated, remote attacker to access sensitive information on a targeted system. Updates are available.
A vulnerability in Microsoft Silverlight could allow an unauthenticated, remote attacker to access sensitive information.
The vulnerability is due to improper memory operations performed by the affected software when handling certain objects. An attacker could exploit the vulnerability by convincing a user to follow a malicious link. A successful exploit could allow the attacker to access sensitive on a targeted system.
Functional code that demonstrates an exploit of this vulnerability is publicly available.
Microsoft has confirmed the vulnerability in a security bulletin and released software updates.
Microsoft Silverlight version 5 is affected when running on the following platforms:
All supported releases of Microsoft Windows clients
All supported releases of Microsoft Windows servers
To exploit the vulnerability, the attacker may provide a link that directs a user to a malicious site and use misleading language or instructions to persuade the user to follow the provided link.
Microsoft has resolved this vulnerability by correcting the way that Silverlight handles objects in memory.
Microsoft has released a security bulletin at the following link: MS13-087
An unauthenticated, remote attacker could exploit the vulnerability to access sensitive information on a targeted system.
The vulnerability is in the public WriteableBitmap class from the System.Windows.dll library of the affected software. The affected class performs insufficient sanitization of a user-defined data stream and could read image pixels using the public SetSource() method.
An unauthenticated, remote attacker could exploit the vulnerability by convincing a user to follow a malicious link. Successful exploitation could trigger a memory corruption error and allow the attacker to access sensitive information on a 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.
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.
Version 1, October 8, 2013, 6:24 PM: Microsoft Silverlight contains a vulnerability that could allow an unauthenticated, remote attacker to access sensitive information on a targeted system. Updates are available.
The security vulnerability applies to the following combinations of products.
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