Always On VPN Security Updates July 2025

Patch Tuesday has arrived, and, unlike last month, it’s a busy month for Always On VPN administrators. The June 2025 Microsoft security updates address a whopping 16 (!) vulnerabilities in the Windows Routing and Remote Access Service (RRAS). Notably, DirectAccess administrators are once again impacted by a critical vulnerability in the Windows KDC Proxy Service (KPSSVC) this month.

RRAS

As stated previously, this month’s update addresses 16 unique CVEs in Windows Server RRAS. All are memory-related buffer overflows and out-of-bounds reads, indicating that a security researcher was recently probing for vulnerabilities in RRAS.

While all the above CVEs are Remote Code Execution (RCE) and Information Disclosure vulnerabilities, none are rated as Critical; all are rated as Important. This means exploitation is unlikely, but administrators are encouraged to update as soon as possible.

KDC Proxy

This month’s security update includes another Critical RCE in the Windows KDC Proxy Service (KPSSVC).

The KDC Proxy is enabled by default when DirectAccess is configured. By design, this means the service is exposed to the public Internet, posing a significant risk to organizations using DirectAccess for secure remote access. Administrators are urged to update their systems immediately to avoid compromise.

Additional Information

Microsoft July 2025 Security Updates

Always On VPN Security Updates June 2025

Patch Tuesday is upon us again; thankfully, it’s a light month of Always On VPN administrators. The Microsoft monthly security updates for June 2025 include just a few Windows Routing and Remote Access Service (RRAS) fixes. In addition, an update is available for a vulnerability in the Windows Remote Access Connection Manager. Significantly, DirectAccess administrators are affected this month by a vulnerability identified in the Windows KDC Proxy Service (KPSSVC).

RRAS Updates

The Microsoft security updates for June 2025 address the following CVEs for Windows Server RRAS.

Both RRAS CVEs are Remote Code Execution (RCE) vulnerabilities with max severity ratings of Important.

Remote Access Connection Manager

A security vulnerability in the Windows Remote Access Connection Manager is addressed with the following CVE.

An attacker exploiting this vulnerability could elevate local access privileges.

KDC Proxy

This critical vulnerability affects those organizations still supporting Microsoft DirectAccess in their environments.

This CVE addresses an RCE in the KDC Proxy Service (KPSSVC) that could allow an attacker to execute arbitrary code over the network. DirectAccess administrators are encouraged to apply this update as soon as possible.

Additional Information

Microsoft June 2025 Security Updates

Always On VPN Security Updates April 2025

Microsoft has published its monthly security updates. Many updates address Routing and Remote Access Service (RRAS) vulnerabilities commonly used in Always On VPN deployments. In addition, an update addresses a vulnerability in Active Directory Certificate Services (AD CS). Always On VPN user and device authentication often rely on AD CS-issued certificates.

RRAS Updates

The April 2025 Microsoft security updates include the following CVEs for Windows Server RRAS.

Only one of these CVEs (26668) is a Remote Code Execution vulnerability. The others are information disclosure vulnerabilities. None of these vulnerabilities are rated Critical; all are rated Important.

AD CS Update

This month’s security update includes the following CVE for AD CS.

Additional Information

Microsoft April 2025 Security Updates