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Server Message Block version 1 (SMB v1) network protocol is no longer installed by default in Operating System. It was superseded by SMBv2 and later protocols starting in 2007. Microsoft publicly deprecated the SMBv1 protocol in 2014.
Legacy System Dependencies
However, some legacy systems still depend on Server Message Block and does not work when the server is migrated to a recent operating system where SMB 1.0 is not installed by default. If the server is hosted on-premises, then we can easily install the SMB 1.0 feature in server.
The Azure Cloud Challenge
Recently, one of our clients raised the requirement to install Server Message Block v1.0 feature on one of their server running Windows Server 2016 operating system. This was needed by one of their legacy systems which was unable to access shared files without SMB 1.0. The server was hosted on Azure Cloud. We tried to install SMB 1.0 but failed every time. We did everything by book and supplied the correct source file for installation, yet the feature failed to install.
Microsoft’s Documentation about SMB
We did some research, consulted our friends at Microsoft, and found one of the articles in Microsoft docs which confirmed that SMBv1 is not available in Azure VMs. In fact, this is disabled in Azure VM’s since August 2017 when Microsoft established that this is a bug, a third-party application issue or a by-design behavior.
Azure Security Changes
A while time ago, the Azure security team has driven some changes into the default behavior of Windows operating system images that are available in the Azure gallery. These changes are in response to recent concerns over malware such as WannaCrypt which has been able to take advantage of issues with the Server Message Block Version 1 network file sharing protocol.
Ensuring Security in Azure VMs
This is why after 2017 the VMs in Azure got the Server Message Block v1 disabled by default in order to avoid potential attacks on the resources. You can read more about it in the following Microsoft Docs link: Disabling Server Message Block Version 1 (SMB v1) in Azure | Microsoft Docs.
Security Recommendation
I’d like to offer a sincere piece of advice: Regardless of whether your server operates on-premises or in a cloud environment, it’s highly advisable to avoid the installation of SMB 1.0, the Server Message Block version 1. This seemingly minor choice carries significant consequences. By refraining from using Server Message Block v1.0, you proactively shield your server and, by extension, your entire organization from potential vulnerabilities.
SMB 1.0 has fallen out of favor for several important reasons, not the least of which is its susceptibility to security threats that resemble the infamous WannaCry malware attack. Installing SMB 1.0 can create an unnecessary entry point for malicious actors, exposing your server to vulnerabilities that may compromise your data and disrupt your operations. In today’s digital landscape, where cyber threats are increasingly sophisticated and pervasive, such vulnerabilities are best avoided at all costs.
Modernizing your server infrastructure by transitioning to newer Server Message Block versions, such as SMBv2 or SMBv3, is a more secure and prudent approach. These updated protocols offer enhanced security features and better protection against known vulnerabilities. By making this transition, you align your server environment with contemporary best practices and reduce the risk of being exploited by cyber threats.
In conclusion, safeguarding your organization’s digital assets is of paramount importance. Steer clear of Server Message Block v1.0, and you’ll significantly mitigate the risk of encountering WannaCry-like malware attacks. Instead, prioritize security and consider embracing modern protocols that provide a safer foundation for your server infrastructure. Your commitment to security will pay dividends in the long run, ensuring the uninterrupted and reliable operation of your systems.
