MicrosoftKB5041021July 9, 2024-Security and Quality Rollup for .NET Framework 3.5.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Server 2008 R2 SP1 (KB5041021)
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
AI Score
Confidence
High
EPSS
Percentile
21.7%
July 9, 2024-Security and Quality Rollup for .NET Framework 3.5.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Server 2008 R2 SP1 (KB5041021)
_ Revised August 28, 2024: _ Update breaking change details to known issue section._ Revised July 30, 2024: _ Add breaking change information to known issue section.
Applies to: Microsoft .NET Framework 3.5.1 Microsoft .NET Framework 4.6.2 Microsoft .NET Framework 4.7 Microsoft .NET Framework 4.7.1 Microsoft .NET Framework 4.7.2 Microsoft .NET Framework 4.8
REMINDER Windows Server 2008 R2 SP1 have reached the end of mainstream support and are now in extended security update (ESU) support. Starting in July 2020, there will no longer be optional, non-security releases (known as “C” releases) for this operating system. Operating systems in extended support have only cumulative monthly security updates (known as the “B” or Update Tuesday release). Verify that you have installed the required updates listed in theHow to get this update section before installing this update. Customers who have purchased the Extended Security Update (ESU) for on-premises versions of these operating systems must follow the procedures in KB4522133 to continue receiving security updates after extended support ends on January 14, 2020. For more information on ESU and which editions are supported, see KB4497181. For more information, see the ESU blog.
REMINDER All updates for .NET Framework 4.7.2, 4.7.1, 4.7, 4.6.2, 4.6.1, and 4.6 require that the d3dcompiler_47.dll update is installed. We recommend that you install the included d3dcompiler_47.dll update before you apply this update. For more information about the d3dcompiler_47.dll, see KB 4019990. If you install a language pack after you install this update, you must reinstall this update. Therefore, we recommend that you install any language packs that you need before you install this update. For more information, see Add language packs to Windows.
Summary
Security Improvements CVE-2024-38081 - .NET Framework Elevation of Privilege Vulnerability
This security update addresses a remote code execution vulnerability detailed in CVE-2024-38081.Quality and Reliability ImprovementsFor a list of improvements that were released with this update, please see the article links in the Additional Information section of this article.
Known issues in this update
| Breaking change details | The .NET Framework servicing update released on July 2024 security and quality rollup - .NET Framework contains a security fix addressed an elevation of privilege vulnerability detailed in CVE 2024-38081. The fix changed System.IO.Path.GetTempPath method return value. If windows version exposes the GetTempPath2 Win32 API, this method invokes that API and returns the resolved path. See the Remarks section of the GetTempPath2 documentation for more information on how this resolution is performed, including how to control the return value through the use of environment variables. The GetTempPath2 API may not be available on all versions of Windows. An observable difference between the GetTempPath and GetTempPath2 Win32 APIs is that they return different values for SYSTEM and non-SYSTEM processes. When calling this function from a process running as SYSTEM it will return the path %WINDIR%\SystemTemp, which is inaccessible to non-SYSTEM processes. This return value for SYSTEM processes cannot be overridden by environment variables. For non-SYSTEM processes, GetTempPath2 will behave the same as GetTempPath, respecting the same environment variables to override the return value.In some scenarios it may be possible to redirect the Temp folder to a different folder using environment variables or other means. Please refer to the official documentation for the GetTempPath2 Win32 API for the most up to date information on this behavior. Please reference to the System.IO.Path.GetTempPath API for more information. |
|---|---|
| Temporary workaround | ⚠️**Warning: **The opt-out will disable the security fix for the elevation of privilege vulnerability detailed in CVE 2024-38081. The opt-out is only for temporary workaround if you’re sure that the software is running in secure environments. Microsoft does not recommend applying this temporary workaround. |
- Option#1: Opt out in a command window by setting the environment variable
- COMPlus_Disable_GetTempPath2=true
- Opiton#2: Opt out globally on the machine by creating a system-wide environment variable and rebooting to ensure all processes observe the change.
- System-wide environment variables can be set by running “sysdm.cpl” from a cmd window, and then navigating to “Advanced -> Environment variables -> System variables -> New”.
Resolution| The API behavior change is by design to address the elevation of privilege vulnerability. Any affected software or application is expected to make code change to adapt to this new design change.
- System-wide environment variables can be set by running “sysdm.cpl” from a cmd window, and then navigating to “Advanced -> Environment variables -> System variables -> New”.
Additional information about this update
The following articles contain additional information about this update as it relates to individual product versions.
- 5039909 Description of the Security and Quality Rollup for .NET Framework 3.5.1 for Windows Server 2008 R2 SP1 (KB5039909)
- 5039882 Description of the Security and Quality Rollup for .NET Framework 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows Server 2008 R2 SP1 and Windows Server 2008 SP2 (KB5039882)
- 5039891 Description of the Security and Quality Rollup for .NET Framework 4.8 for Windows Server 2008 R2 SP1 (KB5039891)
How to get this update
| Release Channel | Available | Next Step |
|---|---|---|
| Windows Update and Microsoft Update | Yes | None. This update will be downloaded and installed automatically from Windows Update. |
| Microsoft Update Catalog | Yes | To get the standalone package for this update, go to the Microsoft Update Catalog website. |
| Windows Server Update Services (WSUS) | Yes | This operating system update will offer, as applicable, and individual .NET Framework product updates will be installed. For more information about individual .NET Framework product updates see additional information about this update section. This update will automatically sync with WSUS if you configure as follows: Product: Windows Server 2008 R2 Service Pack 1, Windows Embedded Standard 7 Service Pack 1, Windows Embedded POSReady 7, Windows 7 Professional for Embedded SystemsClassification: Security Updates |
How to obtain help and support for this update
- Help for installing updates: Windows Update FAQ
- Protect yourself online and at home: Windows Security support
- Local support according to your country: International Support
Related
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
AI Score
Confidence
High
EPSS
Percentile
21.7%