Always On VPN at TechMentor 2023

I’m excited to announce that I’ll be presenting at this year’s TechMentor IT training conference! The event takes place July 17-21, 2023, at the Microsoft headquarters in Redmond, Washington.

My Sessions

I will be delivering two talks at this year’s event.

TT04 – Deploying On-premises Certificates using Intune

In this talk, I’ll describe in detail how to deliver on-premises enterprise PKI certificates using Intune. We’ll cover all aspects of certificate delivery, including the Intune Certificate Connector configuration, device configuration profile options, advantages of PKCS over SCEP, and certificate template security best practices.

TT07 – Windows Always On VPN: Notes from the Field

During this session, I’ll share many tips, tricks, and best practices for deploying and managing Always On VPN client configuration settings using Intune. I’ll explain the limitations of the Intune VPN profile template and how to work around them using custom XML. I will also describe how to use Intune Proactive Remediation to optimize Always On VPN client configuration settings post deployment.

Discount Code

Use the discount code Hicks and receive $400.00 off the standard pricing for the event. Don’t miss out on this opportunity to learn from some of the best IT pros in the business. Register today!

Let’s Connect!

If you’re attending TechMentor 2023 this year, let’s connect! I’ll be at the conference all week. Attend one of my sessions, join me on Thursday for a Table Topic lunch, or let’s grab a beer somewhere. Reach out to me and arrange some time!

Always On VPN RRAS and Stale Connections

Always On VPN Updates for RRAS and IKEv2

Always On VPN administrators may be familiar with an issue that affects Windows Server Routing and Remote Access Service (RRAS) servers, where many stale VPN connections appear in the list of active connections. The issue is most prevalent when using IKEv2, either for the Always On VPN device tunnel or the user tunnel. Typically, this does not cause problems, but some administrators have reported issues related to port exhaustion or failed IKEv2 connections when many stale connections are present. Stale connections happen so frequently that I created a PowerShell script to clean them up on the RRAS server. Restarting the RemoteAccess service or rebooting the server also clears stale connections.

Microsoft Fix

Thankfully, Microsoft has addressed these issues in Windows Server 2019 and Windows Server 2022 this month. An update is now available in the March 2023 security update that resolves this problem.

You can find more information about the updates here.

The update was not made available for Windows Server 2016, however. Organizations are encouraged to upgrade to Windows Server 2019 or later to address this problem.

Additional Information

Always On VPN Updates for RRAS and IKEv2

Always On VPN IKEv2 Load Balancing and NAT

Always On VPN and IKEv2 Fragmentation

Always On VPN NPS and PEAP Vulnerabilities

The February 2023 security updates for Windows Server address multiple vulnerabilities that affect Microsoft Always On VPN administrators. This latest update addresses multiple critical and important vulnerabilities in the Network Policy Server (NPS), commonly used to perform RADIUS authentication for Always On VPN servers. Specifically, there are several Remote Code Execution (RCE) and Denial of Service (DoS) vulnerabilities with Protected Extensible Authentication Protocol (PEAP). PEAP with user authentication certificates is the authentication protocol of choice for Always On VPN user tunnel authentication.

Vulnerabilities

The following is a list of vulnerabilities in PEAP addressed in the February 2023 security update.

  • CVE-2023-21689 – Microsoft PEAP Remote Code Execution Vulnerability (critical)
  • CVE-2023-21690 – Microsoft PEAP Remote Code Execution Vulnerability (critical)
  • CVE-2023-21691 – Microsoft PEAP Information Disclosure vulnerability (important)
  • CVE-2023-21692 – Microsoft PEAP Remote Code Execution Vulnerability (critical)
  • CVE-2023-21695 – Microsoft PEAP Remote Code Execution Vulnerability (important)
  • CVE-2023-21701 – Microsoft PEAP Denial of Service Vulnerability (important)

Mitigation

Unauthenticated attackers can exploit the RCE vulnerabilities in PEAP on Microsoft Windows NPS servers. However, NPS servers should not be exposed directly to the Internet and would require an attacker to have access to the internal network already. However, administrators are advised to apply this update to their NPS servers as soon as possible. In addition, organizations that deploy the NPS role on enterprise domain controllers should update immediately.

Additional Information

February 2023 Update for Windows Server 2022 (KB5022842)

February 2023 Update for Windows Server 2019 (KB022840)

February 2023 Update for Windows Server 2016 (KB5022838)