How to disable SMB v1 (Server Message Block) (2024)

FAQs

How to disable SMB v1 (Server Message Block)? ›

Step 1: Open control panel Step 2: Navigate to programs and features. Step 3: Click on "Turn Windows features on or off. Step 4: Disable "(Server Message Block) SMB v1"Step 5 : Click ok.

In Control Panel, select Programs and Features. Under Control Panel Home, select Turn Windows features on or off to open the Windows Features box. In the Windows Features box, scroll down the list, clear the check box for SMB 1.0/CIFS File Sharing Support and select OK.

Newer operating systems will have SMBv1 disabled by default. The filer will use SMB1 as default. The below option will enable smb2 connection with the DC.

To disable SMB signing in Group Policy, perform the following steps: Select Start, type gpedit. msc, then hit Enter . In the Local Group Policy Editor, navigate to Computer Configuration\Windows Settings\Security Settings\Local Policies\Security Options.

1. Go to Protocols > Windows Sharing (SMB) > Server Settings. 2. In the Encryption section, under Enable encryption on encryption-capable SMB clients, select Use Custom.

Under the More Windows features panel, scroll to the SMB Direct selection and ensure it is checked. You may need to restart your Windows system after performing this change for it to take effect. The SMB 1.0 CIFS File Sharing choice, shown immediately above SMB Direct, should not be enabled.

Security concerns

Microsoft has advised customers to stop using SMBv1 because it is extremely vulnerable and full of known exploits. WannaCry, a well-known ransomware attack, exploited vulnerabilities in the SMBv1 protocol to infect other systems. Because of the security risks, support for SMBv1 has been disabled.

Microsoft is beginning the final phase of disabling SMB1 in Windows, announcing that SMB1 is now disabled by default for Windows 11 Home Insiders, and the company will remove the SMB1 binaries and the drivers and DLLs of SMB1 in future releases.

"SMB 1.0/CIFS Automatic Removal" is a feature which will automatically remove SMB 1.0 after 15 days. Basically if SMB 1.0 gets installed somehow (either manually here, or by some software) then it will get removed after not being used.

How do I disconnect from SMB? ›

Removing an SMB share forcibly disconnects all of the existing connections to the share. Use this cmdlet with caution. Clients that are forcibly disconnected from a share are not able to flush locally cached data before they are disconnected. This may cause data loss.

At Control Panel > File Services > SMB Settings, you can enable this function to browse files on your Synology NAS via Windows Explorer or mount shared folders as network drives.

Step 1: Open control panel Step 2: Navigate to programs and features. Step 3: Click on "Turn Windows features on or off. Step 4: Disable "(Server Message Block) SMB v1"Step 5 : Click ok.

Disabling and enabling SMB Direct features

As SMB Direct is enabled by default, once disabled, it needs to be manually re-enabled whenever needed. Typically, you won't need to disable SMB Direct, however, you can disable it along with its features, by running the following Windows PowerShell commands.

The Microsoft Server Message Block 1.0 (SMBv1) allows denial of service when an attacker sends specially crafted requests to the server, aka "Windows SMB Denial of Service Vulnerability".

Version 1.0 of SMB contains a bug that can be used to take over control of a remote computer. The US National Security Agency (NSA) developed an exploit (called “EternalBlue”) for this vulnerability which was subsequently leaked.