Azure File Sync Agent v17.1 Release - February 2024 (Security-only update)

Improvements and issues that are fixed

• Fixes an issue that might allow unauthorized users to create new files in locations they are not allowed to. This is a security-only update. For more information about this vulnerability, see CVE-2024-21397.

More information about the Azure File Sync Agent v17.1 release

• This security update is available for Windows Server 2012 R2, Windows Server 2016, Windows Server 2019, and Windows Server 2022 installations.

• Windows Server 2012 R2 requires .NET Framework version 4.6.2 or higher.

• Agent support for Windows Server 2012 R2 will end on March 4, 2025. See Windows Server 2012 R2 agent support section below for more information.

• The agent version for this release is 17.1.0.0.

How to obtain and install the Azure File Sync Agent 

The Azure File Sync agent is available from Microsoft Update & Microsoft Update Catalog.

Notes

• Agent v17.1 version is only for upgrades for existing agent installations with agent version v17 and will not be available in Microsoft Download Center.

• To update existing agent installations, download and install the update from Microsoft Update or Microsoft Update Catalog.

• AfsUpdate.exe will not work for v17.1 agent installation.

Microsoft Update

To obtain and install from Microsoft Update, follow these steps on a server that has Azure File Sync agent installed:

Windows Server 2022, Server 2019 and Server2016

1. Click Start, and then click Settings.

2. In Settings, click Update & security.

3. In the Windows Update window, click Check online for updates from Microsoft Update.

4. Verify the Azure File Sync agent update is listed and then click Install now.

Server 2012 R2

1. Click Start, and then click Control Panel.

2. In Control Panel, double-click Windows Update.

3. In the Windows Update window, click Check for updates.

4. Click Important updates are available.

5. Verify the Azure File Sync agent update is selected, and then click Install.

Microsoft Update Catalog

Go to the following website to manually download this update from the Microsoft Update Catalog:

Azure File Sync Agent v17.1 release: February 2024 (KB5023054)

To manually install the update package, extract the cab file and run the following command from an elevated command prompt:

msiexec.exe /p packagename.msp REINSTALLMODE=OMUS REINSTALL=StorageSyncAgent,StorageSyncAgentAzureFileSync,StorageSyncAgentGuardFilter,StorageSyncAgentUpdater /qb /l*v KB5023054.log

For example, to install the Azure File Sync agent update for Server 2016, run the following command:

msiexec.exe /p StorageSyncAgent_WS2016_KB5023054.msp REINSTALLMODE=OMUS REINSTALL=StorageSyncAgent,StorageSyncAgentAzureFileSync,StorageSyncAgentGuardFilter,StorageSyncAgentUpdater /qb /l*v KB5023054.log

Windows Server 2012 R2 agent support will end on March 4, 2025

Windows Server 2012 R2 reached end of support on October 10, 2023. Azure File Sync will continue to support Windows Server 2012 R2 until the v17.x agent is expired on March 4, 2025. Once the v17 agent is expired, Windows Server 2012 R2 servers will stop syncing to your Azure file shares.

Action Required

Perform one of the following options for your Windows Server 2012 R2 servers prior to v17 agent expiration on March 4, 2025:

• Option #1: Perform an in-place upgrade to a supported operation system version. Once the in-place upgrade completes, uninstall the Azure File Sync agent for Windows Server 2012 R2, restart the server and install the agent for the new server operating system (Windows Server 2016, Windows Server 2019, or Windows Server 2022).

• Option #2: Deploy a new Azure File Sync server that is running a supported operation system version to replace your Windows 2012 R2 servers. For more guidance, see Replace an Azure File Sync server.

Note: Azure File Sync agent v17.3 is the last agent release currently planned for Windows Server 2012 R2. To continue to receive product improvements and bug fixes, upgrade your servers to Windows Server 2016 or later.