Microsoft Security Bulletin MS07-032 - Moderate

Mitigation refers to a setting, common configuration, or general best-practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factor may be helpful in your situation:

An attacker must have valid logon credentials.

We have not identified any workarounds for this vulnerability.

What is the scope of the vulnerability?
This is an information disclosure vulnerability. A local attacker who successfully exploited this vulnerability could use the information to gain valid logon credentials. An attacker using compromised logon credentials could then gain access to additional data available to other user accounts or potentially be used take complete control of an affected system.

What causes the vulnerability?
On Windows Vista, permissions on certain user information stores in the registry and local file system are set by default to a level that may allow a low-privileged users unnecessary access.

What might an attacker use the vulnerability to do?
An attacker who successfully exploited this vulnerability could take complete control of the affected system, or access any data available to compromised user accounts.

How could an attacker exploit the vulnerability?
An attacker would have to logon locally to an affected system and identify the information data stores.

Could the vulnerability be exploited over the Internet?
No. This vulnerability can only be exploited by locally authenticated users with local access to the affected system.

What systems are primarily at risk from the vulnerability?
Any Windows Vista system. Windows Vista systems that have been upgraded from Windows XP may be at more risk because of additional information that is stored as a result of the upgrade process.

What does the update do?
The update addressees the vulnerability by removing unprivileged users’ access to the confidential information data stores contained in the local files system. The data stores are as a result restricted to users only with Administrator access.

When this security bulletin was issued, had this vulnerability been publicly disclosed?
No. Microsoft received information about this vulnerability through responsible disclosure.

When this security bulletin was issued, had Microsoft received any reports that this vulnerability was being exploited?
No. Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers and had not seen any examples of proof of concept code published when this security bulletin was originally issued.

Reference Table

The following table contains the security update information for this software. You can find additional information in the subsection, Deployment Information, in this section.

Installing the Update

When you install this security update, the installer checks whether one or more of the files that are being updated on your system have previously been updated by a Windows hotfix. If you have previously installed a hotfix to update one of these files, the installer will apply the LDR version of this update. Otherwise, the installer will apply the GDR version of the update. For more information about this behavior, see Microsoft Knowledge Base Article 824994.

For more information about the installer, see Microsoft Knowledge Base Article 934307.

For more information about the terminology that appears in this bulletin, such as hotfix, see Microsoft Knowledge Base Article 824684.

This security update supports the following setup switches.

Note You can combine these switches into one command. For backward compatibility, the security update also supports the setup switches that the earlier version of the Setup program uses. For more information about the supported installation switches, see Microsoft Knowledge Base Article 262841. For more information about the Update.exe installer, visit the Microsoft TechNet Web site. For more information about the terminology that appears in this bulletin, such as hotfix, see Microsoft Knowledge Base Article 824684.

Removing the Update

To remove this update, use the Add or Remove Programs tool in Control Panel.

Verifying That the Update Has Been Applied

• Microsoft Baseline Security Analyzer

  To verify that a security update has been applied to an affected system, you may be able to use the Microsoft Baseline Security Analyzer (MBSA) tool. See the section, Detection and Deployment Tools and Guidance, earlier in this bulletin for more information.

• File Version Verification

  Because there are several versions of Microsoft Windows, the following steps may be different on your computer. If they are, see your product documentation to complete these steps.

  1. Click Start, and then click Search.
  2. In the Search Results pane, click All files and folders under Search Companion.
  3. In the All or part of the file name box, type a file name from the appropriate file information table, and then click Search.
  4. In the list of files, right-click a file name from the appropriate file information table, and then click Properties.
     
     Note Depending on the version of the operating system or programs installed, some of the files that are listed in the file information table may not be installed.
  5. On the Version tab, determine the version of the file that is installed on your computer by comparing it to the version that is documented in the appropriate file information table.
     
     Note Attributes other than the file version may change during installation. Comparing other file attributes to the information in the file information table is not a supported method of verifying that the update has been applied. Also, in certain cases, files may be renamed during installation. If the file or version information is not present, use one of the other available methods to verify update installation.