Do you know how many Windows Logon authentications happen on a daily basis? Hundreds of thousands of employees globally use it to access their laptops, desktops, and virtual environments to perform work operations every single day. However, despite widespread adoption of Multi Factor Authentication (MFA) for cloud applications, this critical layer often remains unprotected.
Despite this security challenge being well known, the true reason lies in how difficult it is to enforce MFA across different types of environments. Native solutions, like Windows Hello for Business, can require additional infrastructure, while many virtual desktop platforms often lack any built-in MFA support. In OT and remote locations, enforcing MFA can be even more challenging due to limited connectivity or the inability to use mobile devices.
In this blog, we’ll explore why enforcing MFA for Windows Logon is so challenging and how Silverfort for Windows Logon solution helps overcome these gaps.
Before any work begins: The first step is Windows Logon
We typically see two primary types of Windows Logon in organizations: local Windows Logon and Virtual Desktop Logon:
Local Windows Logon
This is the process of signing in directly to an individual Windows machine using either a local or domain-based account. It’s commonly used on individual devices, work laptops, shared terminals in retail or healthcare industries, and computers in OT environments.
These machines often operate outside the visibility of centralized identity systems, including Active Directory (AD) or modern IdPs. As a result, MFA enforcement is highly inconsistent, especially for local accounts that aren’t connected to any domain, exposing these machines to credential compromise.
Virtual Desktop Logon
In this process, users authenticate into virtual environments like Azure Virtual Desktop, Citrix, or Remote Desktop Protocols (RDP) sessions. While these environments are managed centrally, the initial logon process still relies on Windows authentication layer before any MFA takes place.
Many virtual desktop infrastructures don’t support native MFA at this stage, creating a security gap that attackers can exploit during remote access. Without MFA enforcement, organizations leave critical data and applications exposed to attackers connecting from unmanaged or external devices.
Why enforcing MFA for Windows Logon isn’t so simple
Enforcing MFA across Windows Logon may seem straightforward, but in practice it isn’t just a technical checkbox for security teams. While SaaS applications, cloud workloads and VPNs can be protected with centralized identity providers (IdPs), Windows Logon is often left behind—unmonitored and unprotected.
Unlike cloud applications that rely on centralized SSO platforms, Windows Logon authentication occurs on the endpoint level where MFA enforcement and visibility depend on the underlying infrastructure. In many cases, especially with local or offline machines, this makes it difficult for security teams to apply consistent policies or track authentication activity.
It introduces a different set of challenges based on additional infrastructure requirements, lack of native support for virtual environments, and the reality of offline user scenarios. With these risks in mind, attackers often look for Windows Logon authentication presence in the environment to compromise credentials and start moving laterally with privilege escalation afterwards.
Let’s take a closer look at why protecting Windows Logon with MFA is harder that it seems.
- Additional infrastructure requirements: a barrier for deployment
Protecting Windows Logon with MFA often requires the deployment of additional infrastructure, including certificate-based authentication, public key infrastructure (PKI), or biometric devices enrollment. These components increase the complexity of setup and limit the ability to scale MFA across diverse environments. For organizations with limited workforce or no existing certificate infrastructure, this becomes the bottleneck that either delays or completely prevents any MFA enforcement. As a result, critical authentication layer left exposed because cost and effort of deployment are too high.
- Lack of native support in virtual environments: a security gap for remote access
In virtual desktop environments MFA enforcement is often missing at the initial identity layer. These platforms may support MFA at later stages, such as application access or session initiation, and this creates a blind spot where users can authenticate to the desktop without any additional verifications. For attackers, this is a critical gap in remote access scenarios, allowing credential-based compromise or lateral movement without any MFA trigger.
- Offline and OT environments: no connectivity, no MFA
In many organizations, Windows machines operate in environments where network connectivity is limited or restricted. These include OT systems in factories, industrial control rooms, warehouses, and remote field sites. Within these environments, employees cannot use any traditional MFA methods, including push notifications. As a result, Windows Logon authentications remain completely unprotected and unobserved, leaving critical resources open to compromise.
These challenges leave the Windows Logon layer exposed, making it a prime target for identity-based attacks. That’s why, for many organizations, enforcing MFA at this layer is no longer optional. Cyber insurance policies and compliance frameworks, like CJIS, now require secure authentication at the machine level to protect sensitive data.
How Silverfort extends MFA for Windows Logon
Silverfort allows organizations to enforce MFA across all types of Windows Logon scenarios without requiring additional infrastructure deployed in the environment. By integrating directly at the authentication protocol level, Silverfort applies MFA in real time to both domain-based and local authentications, whether on a physical device, a virtual machine or an offline system.
Let’s explore how Silverfort helps organizations address different use cases of Windows Logon authentication.
Enforcing MFA for Local Windows Endpoints
Silverfort for Windows Logon (S4WL) provides access control and real-time risk analysis for all Windows endpoints to allow users authenticate to the domain of local AD or Microsoft Entra ID. When a user attempts to log in, Silverfort evaluates the request through its policy engine and can trigger a push notification via Entra ID, ensuring the user’s identity is verified before access is granted.
Protecting Virtual Desktop Logon
Silverfort secures RDP sessions by enforcing MFA directly at the Windows Logon layer. In this configuration, when a user initiates an RDP connection, they are prompted to enter one-time passcode (OTP) that provides an additional identity layer of verification before granting access to remote machines or servers.
Securing offline and OT environments
In environments where internet connectivity is limited or unavailable, such as OT systems in factories or field sites, Silverfort supports offline Windows Logon by evaluating authentication attempts locally and prompting users to authenticate with a FIDO2 hardware token or a TOTP code.
Preventing identity-based attacks from the first login
Windows Logon is one of the most common first access points used across any organization. Without protection at this critical layer, attackers can easily exploit credentials to move laterally and escalate privileges undetected. Silverfort helps close this blind spot by enforcing strong MFA controls on the login authentication process. With end-to-end visibility into every authentication attempt and policy-based access control, Silverfort can finally help security teams prevent identity-based attacks.
Looking to secure your Windows Logon authentications? Schedule a call with one of our experts to see how Silverfort can help you secure your environment.