How to Completely Disable ‘Insecure Private Network Requests’ via Group Policy in Microsoft Edge

Modern web browsers like Microsoft Edge implement strict Cross-Origin Resource Sharing (CORS) policies to govern how web applications interact with different domains. However, a specific attack vector exists known as “Private Network Access” (or DNS Rebinding), where a malicious script loaded from a public website (e.g., https://malicious.com) attempts to silently query local, private network IP addresses (e.g., 192.168.1.1 or localhost) running insecure HTTP services. This allows external websites to scan local networks, exploit vulnerable routers, or interact with unauthenticated local daemons running on the user’s machine. While Microsoft Edge is actively working towards blocking these by default, legacy compatibility often permits these insecure private network requests.

This guide explains how to completely disable ‘Insecure Private Network Requests’ via Group Policy in Microsoft Edge, enforcing a strict cryptographic block that prevents public internet contexts from initiating unauthorized connections to your internal local area network infrastructure.

Disable Insecure Private Network Requests via Group Policy

To enforce a strict configuration that hardens the Chromium networking stack against local network scanning and DNS rebinding attacks, we must deploy an administrative template that explicitly mandates Secure Contexts for all Private Network Access.

1. Log into Windows with an Administrator account.
2. Press the Windows Key + R to open the Run dialogue box.
3. Type gpedit.msc and press Enter to launch the Local Group Policy Editor.
4. In the left-hand navigation pane, strictly follow this exact path:

   Computer Configuration > Administrative Templates > Microsoft Edge

5. In the right-hand pane, locate the policy named Block insecure private network requests (internally known as InsecurePrivateNetworkRequestsAllowed).
6. Double-click the policy to open its configuration window.
7. Select the radio button next to Enabled. (By explicitly enabling this restriction policy-which acts as a boolean block-we instruct the Chromium engine to instantly reject any fetch, XHR, or navigation request initiated from a public IP space targeting a private or loopback IP space unless the request is cryptographically secured via HTTPS).
8. Click Apply, then click OK.

Verify the Configuration Lockdown

Group Policy changes modifying the Chromium networking stack require the browser to restart to instantiate the new security baseline.

Close all active instances of Microsoft Edge. To force the policy update immediately across the OS, open Command Prompt as Administrator and run gpupdate /force. To verify the restriction is active, launch Microsoft Edge and navigate to edge://policy. You will see InsecurePrivateNetworkRequestsAllowed set to false. Furthermore, if you attempt to load a public test site designed to initiate a local XHR request to localhost:8080, the Edge Developer Tools (F12) Network tab will instantly show the request blocked with a CORS_ERROR or ERR_NETWORK_ACCESS_DENIED, confirming that your local infrastructure is fully shielded from public web scripts.