Microsoft pushes emergency fix for Hyper-V freeze bug on Windows Server 2022

Microsoft has released an emergency fix for Windows Server 2022 to stop Hyper-V virtual machines from freezing or restarting without warning.

It’s worth noting that Azure confidential VMs mostly face this issue, as they’re built to secure data during processing. The freezes happen due to how the system handles memory paths using guest physical addresses (GPA). The bug could cause VMs to lock up or reboot randomly, impacting uptime and requiring manual fixes.

To solve this, Microsoft issued KB5061906 as an out-of-band update. It replaces all earlier patches and targets a specific problem in the Hyper-V direct send path. According to Microsoft, this update mostly matters to Azure confidential VMs and shouldn’t affect standard Hyper-V setups, unless you’re using preview builds or test environments.

You can fix the Windows Server 2022 Hyper-V freeze via manual update

The fix won’t show up through Windows Update. If your servers are affected, you’ll need to download and install the standalone MSU package from the Microsoft Update Catalog.

Microsoft says if you haven’t deployed the May 2025 Patch Tuesday update (KB5058385), and your servers run Hyper-V on Windows Server 2022, you should apply KB5061906 instead. But if you’re not affected, there’s no need to install it.

This isn’t the first time Hyper-V has had issues. Microsoft has released several emergency patches over the past two years to fix broken container launches, boot failures, and VM startup errors in both Windows Server 2019 and 2022.