What is the easiest and safest way to detect if SMBv1 is being used? (2024)

FAQs

What is the easiest and safest way to detect if SMBv1 is being used? ›

You can detect SMBv1 status, without elevation, by running: Get-SmbServerConfiguration | Format-List EnableSMB1Protocol .

SMB1 - Audit Active Usage using Message Analyzer

I would check on your servers , if they have got it then turn it off. Give it about 10 mins or so , then you will find out what devices are using it. I usually check the active SMB sessions on the servers to try and determine what might be affected.

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.

Check SMB status: Check the status of the SMB service by running the command "Get-Service -Name "LanmanServer"" in PowerShell. This command will display the status of the LanmanServer service, which is responsible for the SMB protocol.

The SMBv1 protocol is not safe to use. By using this old protocol, you lose protections such as pre-authentication integrity, secure dialect negotiation, encryption, disabling insecure guest logins, and improved message signing.

You can detect SMBv1 status, without elevation, by running: Get-SmbServerConfiguration | Format-List EnableSMB1Protocol .

Server Message Block (SMB) is a network protocol used by Windows-based computers to provide files and printer sharing services between computers in a network. SMBv1 is a legacy protocol that uses the MD5 (Message Digest) algorithm, which is known to be vulnerable to a number of attacks.

Cifs option shows SMBv1 is disabled by default.

While port 139 and 445 aren't inherently dangerous, there are known issues with exposing these ports to the Internet. You can check if a port is open by using the netstat command.

How to test SMB connection from Windows? ›

The first version of the protocol – SMB v1 – was full of vulnerabilities that could be easily exploited. Today, the updated protocol is more secure, but SMB v1 exploits continue to happen because many machines still use the old and much more insecure protocol.

1 — the latest version of SMB — was released along with Windows Server 2016 and Windows 10. SMB 3.1. 1 includes security enhancements such as: enforcing secure connections with newer (SMB2 and later) clients and stronger encryption (AES-256 from Windows 11 and Windows Server 2022).

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.

Test SMB Connection:

You can use the `Test-NetConnection` cmdlet to test the SMB connection. This command can check for a TCP/IP connection to a specified port, like 445 for SMB. Replace `FileServerName` with the actual name or IP address of your file server.

CMD Find File Name Containing a String

The /s switch tells the command to search in all subdirectories, and the /b switch tells it to display only the bare file name.

In the Local Group Policy Editor, navigate to Computer Configuration\Windows Settings\Security Settings\Local Policies\Security Options. Open Microsoft network client: Digitally sign communications (always), select Enabled, then select OK.