Azure Conditional Access Certificates with SID Information Now Available

I recently wrote about changes to certificate-based authentication affecting Always On VPN implementations. These changes were introduced by Microsoft’s security update KB5014754. When the update is installed on domain controllers and enterprise Certification Authorities (CAs), administrators can perform strong user mapping for certificates used for Active Directory authentication. However, when first introduced, the update came with some serious limitations that prevented administrators from enabling full enforcement mode for certificate mapping.

Limitations

When KB5014754 is installed on an enterprise issuing CA, a new certificate extension (1.3.6.1.4.1.311.25.2) is added to the issued certificate that includes the principal’s (user or device) Security Identifier (SID). However, this only occurs when an online template is used. An online template is one with the subject name built from Active Directory information. The SID is not embedded in certificates issued using an offline template. Offline templates are templates where the subject name is supplied in the request. There are two scenarios where this causes problems for Always On VPN.

Microsoft Intune

Certificates delivered with Microsoft Intune via the Intune Certificate Connector use an offline template. This applies to certificates using PKCS or SCEP. Today, the SID is not embedded by issuing CAs using offline templates.

Azure Conditional Access

The short-lived certificate issued by Azure when Conditional Access is configured for Always On VPN did not include the SID. However, that recently changed.

Recent Updates

Today we can scratch Azure Conditional Access off the list of limitations for Always On VPN. Microsoft recently introduced support for the new SID extension in Azure Conditional Access certificates, as shown here.

Now when an Azure Conditional Access certificate is issued to an on-premises user or device account that is synced with Azure Active Directory, Azure Conditional Access will include the SID information in the issued short-lived certificate.

Intune

Unfortunately, we’re still waiting for Microsoft to address the limitation with certificates delivered using Microsoft Intune. Hopefully we’ll see an update for that later this year.  

Additional Information

Certificate-Based Authentication Changes and Always On VPN

Microsoft KB5014754

Digital Certificates and TPM

Microsoft Intune Certificate Connector Service Account and PKCS

Endpoint Manager and Intune Learning Resources for Always On VPN Administrators

Microsoft Endpoint Manager (MEM), formerly Intune, is the recommended solution for deploying and managing Windows Always On VPN client configuration settings. Always On VPN is designed for Mobile Device Management (MDM), with configuration settings deployed specifically to the VPNv2 Configuration Service Provider (CSP) interface.

Resources

Getting up to speed on all things MEM isn’t difficult at all. I’ve found the MEM community to be exceedingly helpful, and there are many available training resources in various formats from which to choose.

Books

The following is a list of Microsoft Endpoint Manager books Always On VPN administrators will find most helpful for learning about MEM.

YouTube

The Intune Training channel on YouTube is an incredibly valuable resource for Always On VPN administrators learning MEM. Hosted by Steven Hosking, Adam Gross, and Ben Reader, there are countless videos covering important MEM configuration tasks.

Pluralsight

Pluralsight offers video training courses for a wide variety of IT-related topics. Recently I published the  Implementing Always On VPN video training course. There are several Microsoft Endpoint Manager video training courses available as well. Pluralsight is available via subscription. You can sign up for a free trial here if you don’t have a subscription.

Conferences

The Midwest Management Summit (MMS) is the premier event for systems management professionals. Their annual conference takes place each spring in the U.S. (Minneapolis, MN). The event is the best place to learn about Microsoft Endpoint Manager and network with systems management professionals worldwide.

Additional Resources

As a reminder, MEM topics such as certificate deployment and Always On VPN profile deployment and management are covered in detail in both my Implementing Always On VPN book and the Implementing Always On VPN video training course on Pluralsight. 😁

Always On VPN at MMSMOA 2022

I am excited to announce that I will be presenting at this year’s Midwest Management Summit at the Mall of America (MMSMOA) in Bloomington, Minnesota. The conference takes place the week of May 2. This is my first time presenting at this event, and I’m looking forward to sharing my experience deploying enterprise mobility and security infrastructure solutions with systems management professionals from around the world.

Sessions

I will be delivering three talks at the conference addressing various secure remote access and certificate services topics.

Managing Always On VPN with Intune

This session will provide administrators with everything they need to know about provisioning and managing Always On VPN client configuration settings using Intune. I’ll be providing tips, tricks, and best practices for Always On VPN profile configuration and demonstrating many of the limitations associated with using Intune. I will provide workarounds whenever possible.

Managing Always On VPN with Intune: The Good, The Bad, and the Ugly

Always On VPN Gateway Options in Azure

Deploying Always On VPN in Azure is increasingly common. However, administrators are unaware of the limitations of supporting Always On VPN connections with native Azure VPN gateway solutions. In this session, I’ll describe in detail what’s required to support Always On VPN and, importantly, what the limitations are.

Always On VPN Gateway Options in Azure

Deploying On-premises PKI Certificates with Intune

As organizations continue to migrate applications, services, and infrastructure to the cloud, the requirement for endpoints to be joined to an on-premises domain is fading. Moving to full Intune management and native Azure Active Directory join for endpoints is increasingly common. However, deploying enterprise PKI certificates o these endpoints is often required. This session will provide detailed guidance for choosing the best solution to deliver on-premises certificates to Azure AD joined devices using Intune.

Deploying on-premises PKI Certificates with Intune

Let’s Connect

I’m looking forward to meeting so many folks who have helped me get up to speed with Microsoft Endpoint Manager/Intune over the years. If you’re attending the conference, or if you are in the area, be sure to reach out. Let’s grab a beer and chat!

Additional Information

Midwest Management Summit at Mall of America (MMSMOA) 2022

Managing Always On VPN with Intune: The Good, The Bad, and the Ugly

Always On VPN Gateway Options in Azure

Deploying on-premises PKI Certificates with Intune