Applies To.NET Framework 4.5

View products that this article applies to.

Summary

This update resolves a vulnerability in the Microsoft .NET Framework that could allow information disclosure if an attacker sends a specially crafted web request to an affected server that has custom error messages disabled. An attacker who successfully exploits the vulnerability would be able to view parts of a web configuration file that could expose sensitive information. To learn more about the vulnerability, see Microsoft Security Bulletin MS15-041. Important To install this update, you must have Windows Installer 3.1 or a later version installed on the computer.Note To resolve the vulnerability, you may need to apply multiple updates depending on the versions of .NET Framework you are running. For more information, see Affected versions of .NET Framework by this security bulletin.

How to obtain and install the update

Method 1: Windows Update

This update is available through Windows Update. When you turn on automatic updating, this update will be downloaded and installed automatically. For more information about how to turn on automatic updating, see Get security updates automatically.

Method 2: Microsoft Download Center

You can obtain the stand-alone update package through the Microsoft Download Center. Follow the install instructions on the download page to install the update.DownloadDownload (KB3037581)

More Information

Command-line switches for this updateLearn about the various command-line switches that are supported by this Microsoft .NET Framework update.

Restart requirementsThis update does not require a system restart after you apply it unless files that are being updated are locked or are being used.

Removal informationNote We do not recommend that you remove any security update.To remove this update, follow these steps:

  1. Open the Programs and Features item in Control Panel.

  2. Click View installed updates.

  3. Select update 3037581.

  4. Click Uninstall.

Replacement informationThis security update replaces previously released update 2901126.

The English (United States) version of this update installs files that have the attributes that are listed in the following tables. The dates and the times for these files are listed in Coordinated Universal Time (UTC). The dates and the times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and the times may change when you perform certain operations on the files.

For all supported x86-based versions of systems

GDR service branch

File name

File version

File size

Date

Time

Aspnet_perf.dll

4.0.30319.34249

41,624

06-Feb-2015

00:48

aspnet_wp.exe

4.0.30319.34249

43,144

06-Feb-2015

00:48

System.Web.ApplicationServices.dll

4.0.30319.34249

62,688

04-Feb-2015

20:26

System.Web.Extensions.dll

4.0.30319.34249

1,850,552

04-Feb-2015

20:26

System.Web.dll

4.0.30319.34249

5,456,528

04-Feb-2015

20:26

System.Web.Mobile.dll

4.0.30319.34249

839,856

04-Feb-2015

20:26

webengine.dll

4.0.30319.34249

24,712

06-Feb-2015

00:48

webengine4.dll

4.0.30319.34249

509,592

06-Feb-2015

00:48

msvcr120_clr0400.dll

12.0.51689.34249

875,688

06-Feb-2015

00:48

LDR service branch

File name

File version

File size

Date

Time

Aspnet_perf.dll

4.0.30319.36285

41,616

04-Feb-2015

14:13

aspnet_wp.exe

4.0.30319.36285

43,152

04-Feb-2015

14:13

System.Web.ApplicationServices.dll

4.0.30319.36285

62,680

04-Feb-2015

13:12

System.Web.Extensions.dll

4.0.30319.36285

1,850,560

04-Feb-2015

13:12

System.Web.dll

4.0.30319.36285

5,457,560

04-Feb-2015

13:12

System.Web.Mobile.dll

4.0.30319.36285

839,848

04-Feb-2015

13:12

webengine.dll

4.0.30319.36285

24,712

04-Feb-2015

14:13

webengine4.dll

4.0.30319.36285

509,576

04-Feb-2015

14:13

msvcr120_clr0400.dll

12.0.52285.36285

875,688

04-Feb-2015

14:13

For all supported x64-based versions of systems

GDR service branch

File name

File version

File size

Date

Time

Aspnet_perf.dll

4.0.30319.34249

45,208

06-Feb-2015

01:01

Aspnet_perf.dll

4.0.30319.34249

41,624

06-Feb-2015

00:48

aspnet_wp.exe

4.0.30319.34249

47,752

06-Feb-2015

01:01

aspnet_wp.exe

4.0.30319.34249

43,144

06-Feb-2015

00:48

System.Web.ApplicationServices.dll

4.0.30319.34249

62,688

04-Feb-2015

20:26

System.Web.Extensions.dll

4.0.30319.34249

1,850,552

04-Feb-2015

20:26

System.Web.dll

4.0.30319.34249

5,450,384

06-Feb-2015

01:01

System.Web.dll

4.0.30319.34249

5,456,528

04-Feb-2015

20:26

System.Web.Mobile.dll

4.0.30319.34249

839,856

04-Feb-2015

20:26

webengine.dll

4.0.30319.34249

26,760

06-Feb-2015

01:01

webengine.dll

4.0.30319.34249

24,712

06-Feb-2015

00:48

webengine4.dll

4.0.30319.34249

621,192

06-Feb-2015

01:01

webengine4.dll

4.0.30319.34249

509,592

06-Feb-2015

00:48

msvcr120_clr0400.dll

12.0.51689.34249

869,536

06-Feb-2015

01:01

msvcr120_clr0400.dll

12.0.51689.34249

875,688

06-Feb-2015

00:48

LDR service branch

File name

File version

File size

Date

Time

Aspnet_perf.dll

4.0.30319.36285

45,200

04-Feb-2015

14:24

Aspnet_perf.dll

4.0.30319.36285

41,616

04-Feb-2015

14:13

aspnet_wp.exe

4.0.30319.36285

47,752

04-Feb-2015

14:24

aspnet_wp.exe

4.0.30319.36285

43,152

04-Feb-2015

14:13

System.Web.ApplicationServices.dll

4.0.30319.36285

62,680

04-Feb-2015

13:12

System.Web.Extensions.dll

4.0.30319.36285

1,850,560

04-Feb-2015

13:12

System.Web.dll

4.0.30319.36285

5,450,888

04-Feb-2015

14:24

System.Web.dll

4.0.30319.36285

5,457,560

04-Feb-2015

13:12

System.Web.Mobile.dll

4.0.30319.36285

839,848

04-Feb-2015

13:12

webengine.dll

4.0.30319.36285

26,760

04-Feb-2015

14:24

webengine.dll

4.0.30319.36285

24,712

04-Feb-2015

14:13

webengine4.dll

4.0.30319.36285

621,192

04-Feb-2015

14:24

webengine4.dll

4.0.30319.36285

509,576

04-Feb-2015

14:13

msvcr120_clr0400.dll

12.0.52285.36285

869,544

04-Feb-2015

14:24

msvcr120_clr0400.dll

12.0.52285.36285

875,688

04-Feb-2015

14:13

Affected versions of .NET Framework by this security bulletin

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