TLS and Microsoft SQL Server 2022

Transport Layer Security (TLS) for SQL Server 2022 has numerous benefits. TLS enhances SQL Server security by providing authentication, encrypting data in transit, ensuring regulatory compliance, and following security best practices. It helps prevent unauthorized access, protects sensitive information, and mitigates interception attacks, making it a critical component of a secure database environment.

Self-Signed Certificates

When installing Microsoft SQL Server 2022 on-premises, a self-signed certificate is automatically created to support Transport Layer Security (TLS) connections to the database. From a security perspective, using unmanaged, self-signed certificates is never a good idea.

Risk

Self-signed certificates are insecure because they are not issued by a trusted Certification Authority (CA), making it impossible to verify the legitimacy of the server. This lack of trust enables attackers to intercept and manipulate data through interception attacks. Additionally, since operating systems do not automatically trust self-signed certificates, users may ignore security warnings, increasing the risk of connecting to malicious or compromised servers.

Enterprise PKI Certificates

For production workloads, security best practices dictate using enterprise PKI-issued and managed certificates, which provide many security benefits.

Authentication

TLS with managed certificates provides a mechanism for server authentication, ensuring that clients connect to a legitimate server and not an impostor. TLS authentication helps mitigate interception attacks where an attacker could potentially impersonate the server. Managed TLS certificates can also be revoked in the event of key compromise.

Data Encryption

Microsoft SQL Server 2022 database servers often store sensitive data, including personal details, financial records, and other confidential business information. TLS ensures that data in transit between the client and the server is encrypted using modern cryptography, which enhances privacy and confidentiality while preventing unauthorized interception and eavesdropping.

Compliance Requirements

Many regulatory frameworks and compliance standards, such as GDPR, HIPAA, or PCI-DSS, require or strongly recommend encrypting data in transit. Enabling TLS on SQL Server helps meet these compliance standards, strengthens internal security protections, and avoids potential penalties.

Security Best Practice

Implementing TLS is considered a fundamental security best practice in network and data communication. It reduces the risk of data breaches and enhances the overall network security posture in the enterprise.

TLS and SQL Server 2022

Microsoft SQL Server 2022 includes critical new options for administrators. The “Force Encryption” and “Force Strict Encryption” flags control how encryption is enforced for client connections, but their behavior and compatibility requirements differ.

Force Encryption

When this setting is enabled, the SQL server will encrypt communication between the client and server using TLS. However, contrary to what the name of the setting implies, it is possible for the server to accept unencrypted connections in some cases. If the client does not support encryption, the connection may still succeed without encryption. Enabling Force Encryption prioritizes encryption but does not strictly enforce it, meaning older clients that do not support encryption can still connect. Administrators can use this setting to ensure backward compatibility for applications that may not support strict encryption policies. However, upgrading applications to support encryption is strongly advised.

Force Strict Encryption

This setting is subtly different than the previous setting. It also ensures that all communication between the client and the server is encrypted without exception. If a client does not support encryption, the connection will be rejected. In addition, this setting enforces enhanced security parameters for the connection, such as certificate validation, more secure TLS cipher suites, and the use of TLS 1.3* when available. Force Strict Encryption is designed for modern security compliance. It is the preferred setting and should be used when all clients are known to support encryption.

* Note: TLS 1.3 is supported with SQL Server 2022 cumulative update 1 or later installed.

Key Differences

The following table summarizes the key differences between Force Encryption and Force Strict Encryption.

Force EncryptionEncourages but does not require encryption. Unencrypted connections may still be allowed.
Force Strict EncryptionRequires encryption for all connections. Clients that do not support encryption will be rejected.

Summary

By securing your Microsoft SQL Server with TLS, you significantly enhance the security, reliability, and trustworthiness of your data management systems. In the next post, I’ll provide detailed step-by-step guidance for enabling and configuring TLS on Microsoft SQL Server 2022 using best security practices.

Additional Information

Step-by-Step Guide: Enable TLS in Microsoft SQL Server 2022

VIDEO: Enable TLS in Microsoft SQL Server 2022

Microsoft SQL Server 2022

When Always On VPN Isn’t

Microsoft Always On VPN is a beautiful thing. VPN profiles are assigned to the user (and, optionally, their device). When users power up their device and log on, they are automatically connected to the corporate network and can access all the applications and data they need on-premises. Until recently, though, end users could disconnect the VPN. Why they would do this is beyond comprehension, but sadly, it happens all too often. When it does, it presents a problem for Always On VPN administrators because they must now rely on the user to re-enable this feature. And until they do, they often suffer productivity loss, and their devices may fall out of compliance.

Connect Automatically

When an Always On VPN profile is provisioned to a user (or a device), the VPN profile has the option to ‘Connect automatically’ enabled by default. Unfortunately, this setting is cleared if a user terminates the VPN.

This setting will remain cleared until the user rechecks the box to enable it. Until then, the VPN will no longer connect automatically.

Workarounds

Instead of relying on the grace of the end user to restore Always On functionality, administrators have a few options to correct this problem programmatically.

Intune Remediation

Administrators can use Intune Remediations to deploy a set of detection and remediation scripts I’ve published to update this setting. Now, administrators can enforce ‘Always On’ VPN connections with the assurance that if the user turns off this feature, it will be quickly re-enabled.

Detect-AutoTriggerDisabledProfile.ps1

Remediate-AutoTriggerDisabledProfile.ps1

SCCM

You can find a standalone version of this script here if you use System Center Configuration Manager (SCCM) or another systems management solution to manage your endpoints.

Clear-AutoTriggerDisabledProfile.ps1

AovpnTools

In addition, you will find the Clear-AutoTriggerDisabledProfile function is included in my AOVPNTools PowerShell module, which can be installed from the PowerShell gallery.

Install-Module -Name AOVPNTools -Force

Disable Disconnect Button

To avoid this pain in the future, Always On VPN administrators can prevent users from disconnecting the VPN using the UI by leveraging the DisableDisconnectButton option in ProfileXML. This setting is supported for both user and device tunnels on Windows 11 and later devices.

Additional Information

AOVPNTools PowerShell Module

AOVPNTools PowerShell Module on GitHub

Always On VPN and Intune Remediations

Troubleshooting Always On VPN Errors 691 and 812

Troubleshooting Always On VPN Errors 691 and 812When configuring Windows 10 Always On VPN using the Routing and Remote Access Service (RRAS) on Windows Server 2012 R2 and Extensible Authentication Protocol (EAP) authentication using client certificates, clients attempting to establish a VPN connection using Internet Key Exchange version 2 (IKEv2) may receive the following error.

“The connection was prevented because of a policy configured on your RAS/VPN server. Specifically, the authentication method used by the server to verify your username and password may not match the authentication method configured in your connection profile.”

Troubleshooting Always On VPN Errors 691 and 812

The event log on the client also records RasClient event ID 20227 stating “the error code returned on failure is 812”.

Troubleshooting Always On VPN Errors 691 and 812

Always On VPN clients using the Secure Socket Tunneling Protocol (SSTP) may receive the following error.

“The remote connection was denied because the user name and password combination you provided is not recognized, or the selected authentication protocol is not permitted on the remote access server.”

Troubleshooting Always On VPN Errors 691 and 812

The event log on the client also records RasClient event ID 20227 stating “the error code returned on failure is 691”.

Troubleshooting Always On VPN Errors 691 and 812

Resolution

These errors can occur when Transport Layer Security (TLS) 1.0 has been disabled on the RRAS server. To restore functionality, enable TLS 1.0 protocol support on the RRAS server. If disabling TLS 1.0 is required for compliance reasons, consider deploying RRAS on Windows Server 2016. TLS 1.0 can be safely disabled on Windows Server 2016 without breaking EAP client certificate authentication for Windows 10 Always On VPN clients.

Additional Information

Windows 10 Always On VPN Hands-On Training

What’s the Difference Between DirectAccess and Windows 10 Always On VPN?

5 Important Things DirectAccess Administrators Should Know About Windows 10 Always On VPN

3 Important Advantages of Windows 10 Always On VPN over DirectAccess 

Windows 10 Always On VPN and the Future of DirectAccess