Virtualization-based Security (VBS) (2024)

Virtualization-based security, or VBS, uses hardware virtualization and the Windows hypervisor to create an isolated virtual environment that becomes the root of trust of the OS that assumes the kernel can be compromised. Windows uses this isolated environment to host a number of security solutions, providing them with greatly increased protection from vulnerabilities in the operating system, and preventing the use of malicious exploits which attempt to defeat protections. VBS enforces restrictions to protect vital system and operating system resources, or to protect security assets such as authenticated user credentials.

One such example security solution is memory integrity, which protects and hardens Windows by running kernel mode code integrity within the isolated virtual environment of VBS. Kernel mode code integrity is the Windows process that checks all kernel mode drivers and binaries before they're started, and prevents unsigned or untrusted drivers or system files from being loaded into system memory. Memory integrity also restricts kernel memory allocations that could be used to compromise the system, ensuring that kernel memory pages are only made executable after passing code integrity checks inside the secure runtime environment, and executable pages themselves are never writable. That way, even if there are vulnerabilities like a buffer overflow that allow malware to attempt to modify memory, executable code pages cannot be modified, and modified memory cannot be made executable.

VBS requires the following components be present and properly configured.

VBS works on VMs that have nested virtualization support. This includes all Gen2 VMs, and Gen1 VMs that support nested virtualization. A list of supported VM series is detailed in the table below.

For more info about Hyper-V, see Hyper-V on Windows Server 2016 or Introduction to Hyper-V on Windows 10. For more info about hypervisor, see Hypervisor Specifications.