CVE-2024-0056

FAQ

According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability?

The attacker must inject themselves into the logical network path between the target and the resource requested by the victim to read or modify network communications. This is called a machine-in-the-middle (MITM) attack.

If I am using System.Data.SqlClient or Microsoft.Data.SqlClient, what do I need to do to be protected from this vulnerability?

Customers developing applications using either the System.Data.SqlClient or Microsoft.Data.SqlClient NuGet Packages need to do the following to be protected:

• If you are using System.Data.SqlClient on .NET Framework you must install the January 2024 update(s) for .NET Framework
• If you are using System.Data.SqlClient on .NET 6, .NET 7, or .NET 8 you must update your NuGet package reference to an updated version as listed in the affected packages.
• If you are using Microsoft.Data.SqlClient, anywhere (.NET 6/7/8, .NET Framework) and you are using a version that is vulnerable you must update your NuGet package reference as listed in the affected packages.

Please see Microsoft Security Advisory CVE 2024-0056 | .NET Information Disclosure Vulnerability.

Please Note: Customers running applications that install either System.Data.SqlClient.dll or Microsoft.Data.SqlClient.dll should contact the application developer for application updates.

According to the CVSS metric, a successful exploitation could lead to a scope change (S:C). What does this mean for this vulnerability?

A successful attack could exploit a vulnerability in the SQL Data Provider which allows the attacker to exploit the SQL Server.

How could an attacker exploit this vulnerability?

An attacker who successfully exploited this vulnerability could carry out a machine-in-the-middle (MITM) attack and could decrypt and read or modify TLS traffic between the client and server. There is no impact to the availability of the attacked machine (A:N).

What security feature is bypassed with this vulnerability?

An attacker might be able to evade the encryption used in a TLS connection.

I am running SQL Server on my system. What action do I need to take?

Update your relevant version of SQL Server. Any applicable driver fixes are included in those updates.

I am running my own application on my system. What action do I need to take?

Update your application to use Microsoft ODBC Driver 17 (or 18) for SQL Server or Microsoft OLE DB Driver 18 (or 19). Update the drivers to the versions listed on this page, which provide protection against this vulnerability.

I am running an application from a software vendor on my system. What action do I need to take?

Consult with your application vendor if it is compatible with Microsoft ODBC Driver 17 (or 18) for SQL Server or Microsoft OLE DB Driver 18 (or 19). Update the drivers to the versions listed in this page, which provide protection against this vulnerability

There are GDR and/or CU (Cumulative Update) updates offered for my version of SQL Server. How do I know which update to use?

• First, determine your SQL Server version number. For more information on determining your SQL Server version number, see Microsoft Knowledge Base Article 321185 - How to determine the version, edition, and update level of SQL Server and its components.
• Second, in the table below, locate your version number or the version range that your version number falls within. The corresponding update is the one you need to install.

Note If your SQL Server version number is not represented in the table below, your SQL Server version is no longer supported. Please upgrade to the latest Service Pack or SQL Server product in order to apply this and future security updates.

What are the GDR and CU update designations and how do they differ?

The General Distribution Release (GDR) and Cumulative Update (CU) designations correspond to the two different servicing options in place for SQL Server baseline releases. A baseline can be either an RTM release or a Service Pack release.

• GDR updates – cumulatively only contain security updates for the given baseline.
• CU updates – cumulatively contain all functional fixes and security updates for the given baseline.

For any given baseline, either the GDR or CU updates could be options (see below).

• If SQL Server installation is at a baseline version, you can choose either the GDR or CU update.
• If SQL Server installation has intentionally only installed past GDR updates, then choose to install the GDR update package.
• If SQL Server installation has intentionally installed previous CU updates, then chose to install the CU security update package.

Note: You are allowed to make a change from GDR updates to CU updates ONE TIME. Once a SQL Server CU update is applied to a SQL Server installation, there is NO way to go back to the GDR update path.

Can the security updates be applied to SQL Server instances on Windows Azure (IaaS)?

Yes. SQL Server instances on Windows Azure (IaaS) can be offered the security updates through Microsoft Update, or customers can download the security updates from Microsoft Download Center and apply them manually.