How to remediate – Windows Wireless SSID (WMI)

1. Introduction

The Windows Wireless SSID (WMI) vulnerability allows an attacker to obtain the wireless network name (SSID) currently associated with a remote computer. This information can aid in identifying targets and potentially mapping out a network’s wireless infrastructure. Systems running Windows are usually affected, particularly those actively connected to a wireless network. A successful exploit could reveal confidential network names, impacting confidentiality.

2. Technical Explanation

This vulnerability occurs because the Windows Management Instrumentation (WMI) interface exposes details about the active wireless connection. An attacker with local access can query WMI to retrieve the SSID. The remote system must have an active wireless connection for this detection to occur; otherwise, no information is revealed. There is currently no known CVE associated with this specific issue.

• Root cause: The WMI interface provides unrestricted access to wireless network details without sufficient security checks.
• Exploit mechanism: An attacker executes a WMI query on the target system to retrieve the SSID of the connected wireless network. For example, using PowerShell or WMIC.
• Scope: Windows operating systems with an active wireless connection are affected. Specific versions have not been identified as particularly vulnerable; it depends on the presence and configuration of the WMI interface.

3. Detection and Assessment

You can confirm a system is vulnerable by checking for the existence of the relevant WMI data. A quick check involves listing wireless network information, while thorough assessment requires scripting to automate detection.

• Quick checks: Use PowerShell to list wireless networks. Get-NetConnectionProfile | Where {$_.ConnectivityState -eq "Connected"} | Select Name
• Scanning: Nessus plugin ID 139274 can detect this issue, but results should be manually verified.
• Logs and evidence: No specific event logs directly indicate this vulnerability. However, monitoring WMI access events may reveal suspicious queries.

Get-NetConnectionProfile | Where {$_.ConnectivityState -eq "Connected"} | Select Name

4. Solution / Remediation Steps

Ensure discovered SSIDs comply with your organisation’s security policies. This is a policy enforcement issue, rather than a technical patch.

4.1 Preparation

• Backups are not required for this remediation. No services need to be stopped.
• Dependencies: A clear wireless network usage policy is needed. Roll back involves reverting any changes made to SSID naming conventions if necessary.
• Change window: This change requires minimal downtime and should be approved by the IT security team.

4.2 Implementation

1. Step 1: Review current wireless network SSIDs on all systems.
2. Step 2: Identify any SSIDs that do not comply with your organisation’s acceptable use policy.
3. Step 3: Change non-compliant SSIDs to meet the required standards.

4.3 Config or Code Example

Before

SSID: "MyHomeNetwork"

After

SSID: "CorporateWireless-BuildingA"

4.4 Security Practices Relevant to This Vulnerability

Several security practices can help mitigate this vulnerability.

• Practice 1: Least privilege – limit user access to wireless network configuration settings.
• Practice 2: Secure defaults – enforce strong and unique SSID naming conventions.

4.5 Automation (Optional)

A PowerShell script can be used to identify systems with non-compliant SSIDs.

# Script to find non-compliant SSIDs
$NonCompliantSSIDs = Get-NetConnectionProfile | Where {$_.ConnectivityState -eq "Connected"} | Where {$_.Name -notmatch "^CorporateWireless.*"} | Select Name
if ($NonCompliantSSIDs) {
  Write-Host "The following SSIDs are non-compliant:"
  $NonCompliantSSIDs | ForEach-Object { Write-Host $_.Name }
} else {
  Write-Host "All SSIDs are compliant."
}

5. Verification / Validation

Confirm the fix by verifying that all systems report compliant SSIDs. A negative test involves checking for previously non-compliant names.

• Post-fix check: Get-NetConnectionProfile | Where {$_.ConnectivityState -eq "Connected"} | Select Name – expected output should only show compliant SSID names.
• Re-test: Re-run the initial PowerShell command to confirm no non-compliant SSIDs are present.
• Monitoring: Monitor WMI access events for unusual queries related to wireless networks.

Get-NetConnectionProfile | Where {$_.ConnectivityState -eq "Connected"} | Select Name

6. Preventive Measures and Monitoring

Update security baselines and policies to prevent this issue.

• Baselines: Update your wireless network usage policy to enforce compliant SSID naming conventions (for example, CIS control 14).
• Pipelines: Include checks in configuration management tools to automatically flag non-compliant SSIDs.
• Asset and patch process: Review wireless network configurations regularly as part of a standard security audit cycle.

7. Risks, Side Effects, and Roll Back

Changing SSIDs may temporarily disrupt user connectivity. A clear communication plan is essential.

• Risk or side effect 1: Temporary loss of wireless connectivity for users. Mitigation: Communicate the change in advance and provide support during the transition.
• Roll back: Revert SSID names to their original values if issues arise.

8. References and Resources

Links related to this exact vulnerability.

• Vendor advisory or bulletin: No specific vendor advisory exists for this issue, as it is a policy enforcement matter.
• NVD or CVE entry: No CVE associated with this specific issue.
• Product or platform documentation relevant to the fix: Get-NetConnectionProfile Documentation