When attempting to access a shared resource on a Windows network, you may encounter the error message: ‘This share requires the obsolete SMB1 protocol.’ This issue arises because the Server Message Block (SMB) protocol, a network file-sharing protocol, has evolved significantly over the years.
SMB1, the first version of the protocol, is now considered outdated and insecure. Modern systems disable SMB1 by default to mitigate security risks, but legacy systems or devices may still rely on it. This paper explores the implications of using SMB1, how to temporarily enable it if absolutely necessary, and the steps to upgrade to a more secure protocol.
The Security Risks of SMB1
SMB1, introduced in the 1980s, lacks the security features found in modern protocols like SMB2 and SMB3. It is vulnerable to several exploits, including the infamous WannaCry ransomware attack, which exploited SMB1 vulnerabilities to spread across networks. **Enabling SMB1 exposes your system to significant risks**, such as unauthorized access, data breaches, and malware infections. Microsoft has deprecated SMB1 and recommends disabling it entirely unless absolutely necessary for legacy compatibility.
Modern versions of Windows, such as Windows 10 and Windows 11, disable SMB1 by default. However, older systems or network-attached storage (NAS) devices may still require it. If you must use SMB1, ensure it is only enabled temporarily and on a secure, isolated network to minimize exposure to potential threats.
How to Temporarily Enable SMB1
If you need to access a resource that requires SMB1, you can enable it temporarily. Follow these steps to enable SMB1 on a Windows system:
- Open the Control Panel and navigate to Programs > Turn Windows features on or off.
- Scroll down and check the box for SMB 1.0/CIFS File Sharing Support.
- Click OK and restart your computer.
After enabling SMB1, access the required resource and then disable SMB1 immediately. To disable it, uncheck the box for SMB 1.0/CIFS File Sharing Support and restart your computer. This minimizes the time your system is exposed to potential vulnerabilities.
Upgrading to a Modern SMB Protocol
To eliminate the need for SMB1, upgrade the shared resource to a modern protocol like SMB2 or SMB3. These protocols offer enhanced security features, including encryption, improved authentication, and better performance. If you control the shared resource, such as a NAS device or server, follow these steps:
- Check the device’s documentation or settings to ensure it supports SMB2 or SMB3.
- Update the device’s firmware or software to the latest version.
- Disable SMB1 in the device’s settings and enable SMB2 or SMB3.
If the shared resource is managed by a third party, contact the administrator and request an upgrade to a modern protocol. Most modern devices and systems support SMB2 or SMB3, making this a feasible solution for most users.
Verifying SMB Protocol Settings
To ensure your system is using the correct SMB protocol, you can verify the settings using PowerShell. Open PowerShell as an administrator and run the following command:
Get-SmbServerConfiguration | Select EnableSMB1Protocol, EnableSMB2Protocol
This command displays whether SMB1 and SMB2 are enabled on your system. If SMB1 is enabled and SMB2 is disabled, consider adjusting the settings to prioritize security. You can disable SMB1 and enable SMB2 using the following commands:
Set-SmbServerConfiguration -EnableSMB1Protocol $false Set-SmbServerConfiguration -EnableSMB2Protocol $true
These commands ensure your system uses the most secure and efficient protocol available.
Best Practices for Network Security
Beyond upgrading the SMB protocol, implementing additional security measures can further protect your network. Use a firewall to restrict access to shared resources and ensure only authorized devices can connect.
Regularly update your operating system and network devices to patch vulnerabilities. Enable network encryption, such as IPsec, to secure data in transit. Finally, educate users about the risks of outdated protocols and the importance of maintaining secure systems.