HomeWinBuzzer NewsInside Windows Server 2025 Preview: Security Enhancements and SMB Protocol Updates

Inside Windows Server 2025 Preview: Security Enhancements and SMB Protocol Updates

Microsoft releases Windows Server 2025 preview with improved security (dMSA) and SMB protocol updates.


has introduced the latest preview build 26212 of Windows Server to participants in the Insider Program. This update, part of the Windows Server 2025 rollout, brings new features such as a novel account type and updates to the Server Message Block (SMB) protocol, enhancing both security and management capabilities.

Introduction of Delegated Managed Service Accounts Enhances Security

The new Delegated Managed Service Accounts (dMSA) represent an advancement in server account management by transitioning from traditional service accounts to machine accounts with managed, fully randomized keys. This development boosts security by tying authentication more closely to device identity, ensuring that only designated machine identities in Active Directory have access to the account. This update addresses vulnerabilities such as credential harvesting through compromised accounts, commonly exploited via kerberoasting.

Updates to Server Message Block Protocol

Microsoft has also rolled out updates to the Server Message Block (SMB) protocol, starting with build 26097. These updates include options for administrators to disable SMB over QUIC client and server settings through Group Policy and PowerShell. The changes also introduce auditing capabilities for successful SMB over QUIC connections and support for SMB signing and encryption, which improve oversight and compliance.

Preview Build Challenges and Expiration

The preview build, while introducing promising features, presents known issues such as upgrade difficulties and VM boot problems. Microsoft is addressing these challenges and recommends not using this build for upgrades from Windows Server 2019 or 2022 due to potential upgrade failures. The preview is set to expire on September 15, 2024, and is available for download in various formats and languages.

As the development of Windows Server 2025 continues, Microsoft is expected to introduce further enhancements and fixes to strengthen its suitability for enterprise environments. Windows Server 2025 is the upcoming long term servicing channel release of Microsoft's Windows Server operating system. It's slated for release in the second half of 2024 and is currently in the preview stage.

Luke Jones
Luke Jones
Luke has been writing about all things tech for more than five years. He is following Microsoft closely to bring you the latest news about Windows, Office, Azure, Skype, HoloLens and all the rest of their products.