How to remediate – WMI Anti-spyware Enumeration

1. Introduction

The WMI Anti-spyware Enumeration vulnerability allows an attacker with valid Windows credentials to obtain a list of anti-spyware software installed on a remote host. This information can be used for reconnaissance, helping attackers identify potential targets and tailor attacks accordingly. Affected systems are typically older desktop versions of Windows. A successful exploit could lead to reduced confidentiality as the presence or absence of security tools is revealed.

2. Technical Explanation

This vulnerability occurs because the Windows Management Instrumentation (WMI) interface exposes anti-spyware software information through the ‘rootsecuritycenter’ and ‘rootsecuritycenter2’ namespaces. An attacker can query these namespaces to retrieve a list of installed applications. This requires valid credentials for a user account on the target system. There is no known CVE associated with this specific enumeration, but similar WMI queries have been exploited in the past.

• Root cause: The WMI interface allows querying sensitive information without sufficient access control restrictions.
• Exploit mechanism: An attacker connects to a Windows host using valid credentials and executes a WMI query to retrieve anti-spyware software details. For example, they could use PowerShell to execute Get-WmiObject -Namespace rootsecuritycenter -Class AntiSpywareProduct.
• Scope: Affected platforms are older desktop versions of Windows including XP, Vista, and Windows 7. Server operating systems are not affected as these namespaces are unavailable.

3. Detection and Assessment

You can confirm vulnerability by checking for the presence of the relevant WMI namespaces on a target system. A thorough method involves attempting to query the namespaces.

• Quick checks: Use PowerShell to check if the ‘rootsecuritycenter’ namespace exists: Get-WmiObject -Namespace rootsecuritycenter. If it returns an object, the namespace is present.
• Scanning: Nessus plugin ID 10384 can detect this vulnerability. This should be considered an example only as scanner coverage may vary.
• Logs and evidence: There are no specific event logs directly related to this enumeration. However, successful WMI queries might appear in the Windows Event Log under Application and Services Logs/Microsoft/Windows/WMI-Activity.

Get-WmiObject -Namespace rootsecuritycenter

4. Solution / Remediation Steps

The best way to address this vulnerability is to limit access to the affected systems and implement least privilege principles.

4.1 Preparation

• Changes should be implemented during a scheduled maintenance window with appropriate approval from IT management.

4.2 Implementation

1. Step 1: Review user account permissions on the target systems and remove unnecessary access rights. Ensure users only have the privileges required to perform their tasks.
2. Step 2: Implement Group Policy restrictions to limit WMI access for standard users. This can be achieved by configuring ‘Computer ConfigurationWindows SettingsSecurity SettingsLocal PoliciesUser Rights Assignment’ and restricting access to the ‘Access this computer from the network’ policy.

4.3 Config or Code Example

Before

(Default configuration - all users with valid credentials can query WMI)

After

Computer ConfigurationWindows SettingsSecurity SettingsLocal PoliciesUser Rights Assignment: Deny access to this computer from the network for standard user accounts.

4.4 Security Practices Relevant to This Vulnerability

List only practices that directly address this vulnerability type. Use neutral wording and examples instead of fixed advice. For example: least privilege, input validation, safe defaults, secure headers, patch cadence. If a practice does not apply, do not include it.

• Practice 1: Least privilege reduces the impact if an attacker gains access to a compromised account. Limiting user permissions prevents them from performing unauthorized actions.
• Practice 2: Regularly review and update user account permissions to ensure they align with current job roles and responsibilities. This helps prevent unnecessary access rights.

4.5 Automation (Optional)

# PowerShell example to review user permissions on a remote computer
# Replace $computerName with the target system's name
$computerName = "targetsystem"
Get-WmiObject -ComputerName $computerName -Namespace rootcimv2 -Class Win32_GroupUser | Where-Object {$_.Domain -eq "."} | Select-Object Name, GroupComponent
# This script only reviews permissions; it does not automatically modify them.

5. Verification / Validation

Confirm the fix by attempting to query the WMI namespaces with a standard user account. The query should fail.

• Post-fix check: Use PowerShell as a standard user and attempt to execute Get-WmiObject -Namespace rootsecuritycenter -Class AntiSpywareProduct. It should return an access denied error.
• Re-test: Re-run the initial quick check (Get-WmiObject -Namespace rootsecuritycenter) as a standard user. The command should fail with an access denied message.
• Smoke test: Verify that users can still perform their normal tasks, such as accessing network shares and running applications.
• Monitoring: Monitor the Windows Event Log for failed WMI queries from standard user accounts. This could indicate attempted exploitation or misconfigured permissions.

Get-WmiObject -Namespace rootsecuritycenter -Class AntiSpywareProduct (executed as a standard user)

6. Preventive Measures and Monitoring

Suggest only measures that are relevant to the vulnerability type. Use “for example” to keep advice conditional, not prescriptive.

• Baselines: Update security baselines or policies to enforce least privilege principles for WMI access. For example, implement a CIS control related to user account management.
• Pipelines: Add checks in CI/CD pipelines to validate user permissions and ensure they align with defined security standards.
• Asset and patch process: Implement a regular review cycle for user accounts and permissions to identify and address potential vulnerabilities.

7. Risks, Side Effects, and Roll Back

• Risk or side effect 2: Incorrectly configured Group Policy settings could lock out users from accessing the system. Ensure proper planning and documentation.
• Roll back: Restore the original Group Policy settings if issues occur. Revert any changes made to user account permissions.

8. References and Resources

• Vendor advisory or bulletin: No specific vendor advisory is available for this enumeration.
• NVD or CVE entry: No specific CVE entry exists for this enumeration.
• Product or platform documentation relevant to the fix: Microsoft Documentation on WMI Access Control.