Sign in with Microsoft
Sign in or create an account.
Hello,
Select a different account.
You have multiple accounts
Choose the account you want to sign in with.

Summary

This security update resolves vulnerabilities in Windows. These vulnerabilities could allow elevation of privilege if an attacker logs on to the system and runs a specially crafted application. To exploit the vulnerabilities, an attacker would first have to log on to the system. This security update addresses the vulnerabilities by correcting how Windows validates impersonation events. To learn more about the vulnerabilities, see Microsoft Security Bulletin MS15-038.

To resolve the vulnerabilities, you may need to apply multiple updates depending on the version of Windows you are running, see the following table for more information:

Windows version

Updates to install

Windows Server 2003 R2 SP2

3045685

Windows Vista SP2, Windows Server 2008 SP2
Windows 7 SP1, Windows Server 2008 R2 SP1
Windows 8, Windows RT, Windows Server 2012
Windows 8.1, Windows RT 8.1, Windows Server 2012 R2

3045685 and
3045999

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.

Note For Windows RT and Windows RT 8.1, this update is available through Windows Update only.

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

Click the download link in the following table that corresponds to the version of Windows you are running.

Windows version

Download link

Windows Server 2003 R2 Service Pack 2

Download Download 64-bit (KB3045685)

Windows Vista SP2

Download Download 32-bit (KB3045685)
Download Download 64-bit (KB3045685)

Windows Server 2008 SP2

Download Download 32-bit (KB3045685)
Download Download 64-bit (KB3045685)
Download Download Itanium-based (KB3045685)

Windows 7 SP1

Download Download 32-bit (KB3045685)
Download Download 64-bit (KB3045685)

Windows Server 2008 R2 SP1

Download Download 64-bit (KB3045685)
Download Download Itanium-based (KB3045685)

Windows 8

Download Download 32-bit (KB3045685)
Download Download 64-bit (KB3045685)

Windows Server 2012

Download Download 64-bit (KB3045685)

Windows 8.1

Download Download 32-bit (KB3045685)
Download Download 64-bit (KB3045685)

Windows Server 2012 R2

Download Download 64-bit (KB3045685)


More Information

Security update deployment informationFor deployment information about this update, see Microsoft Knowledge Base Article 3049576.

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


Windows Server 2003 R2 file information

  • The files that apply to a specific milestone (SPn) and service branch (QFE, GDR) are noted in the "SP requirement" and "Service branch" columns.

  • GDR service branches contain only those fixes that are widely released to address widespread, critical issues. QFE service branches contain hotfixes in addition to widely released fixes.

  • In addition to the files that are listed in these tables, this software update also installs an associated security catalog file (KBnumber.cat) that is signed with a Microsoft digital signature.

For all supported x64-based versions of Windows Server 2003 R2

File name

File version

File size

Date

Time

Platform

SP requirement

Service branch

Clfs.sys

5.2.3790.5562

366,592

04-Mar-2015

01:11

x64

SP2

SP2QFE

Clfsw32.dll

5.2.3790.5562

105,984

04-Mar-2015

01:11

x64

SP2

SP2QFE

Clfs.sys

5.2.3790.5562

366,592

04-Mar-2015

01:11

x64

SP2

SP2QFE\IA

Clfs.sys

5.2.3790.5562

366,592

04-Mar-2015

01:11

x64

SP2

SP2QFE\ID

Clfs.sys

5.2.3790.5562

366,592

04-Mar-2015

01:11

x64

SP2

SP2QFE\IS

For all supported x86-based versions of Windows Server 2003 R2

File name

File version

File size

Date

Time

Platform

SP requirement

Service branch

Clfs.sys

5.2.3790.5562

204,288

04-Mar-2015

00:54

x86

SP2

SP2QFE

Clfs.sys

5.2.3790.5562

204,288

04-Mar-2015

00:54

x86

SP2

SP2QFE\IA

Clfsw32.dll

5.2.3790.5562

79,360

04-Mar-2015

02:07

x86

SP2

SP2QFE\IA

Clfs.sys

5.2.3790.5562

204,288

04-Mar-2015

00:54

x86

SP2

SP2QFE\ID

Clfsw32.dll

5.2.3790.5562

79,360

04-Mar-2015

02:07

x86

SP2

SP2QFE\ID

Clfs.sys

5.2.3790.5562

204,288

04-Mar-2015

00:54

x86

SP2

SP2QFE\IS

Clfsw32.dll

5.2.3790.5562

79,360

04-Mar-2015

02:07

x86

SP2

SP2QFE\IS

Windows Vista and Windows Server 2008 file information

  • The files that apply to a specific product, milestone (SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table:

    Version

    Product

    Milestone

    Service branch

    6.0.6002.18xxx

    Windows Vista SP2 and Windows Server 2008 SP2

    SP2

    GDR

    6.0.6002.23xxx

    Windows Vista SP2 and Windows Server 2008 SP2

    SP2

    LDR

  • GDR service branches contain only those fixes that are widely released to address widespread, critical issues. LDR service branches contain hotfixes in addition to widely released fixes.

Note The MANIFEST files (.manifest) and MUM files (.mum) that are installed are not listed.

For all supported x86-based versions of Windows Vista and Windows Server 2008

File name

File version

File size

Date

Time

Platform

Clfsw32.dll

6.0.6002.19331

57,344

05-Mar-2015

02:23

x86

Clfsw32.dll

6.0.6002.23639

57,344

05-Mar-2015

01:41

x86

Clfs.mof

Not applicable

3,472

18-Sep-2006

21:38

Not applicable

Clfs.sys

6.0.6002.19331

244,152

05-Mar-2015

02:32

x86

Clfsuninstall.mof

Not applicable

123

18-Sep-2006

21:39

Not applicable

Clfs.mof

Not applicable

3,472

07-May-2014

23:47

Not applicable

Clfs.sys

6.0.6002.23639

244,152

05-Mar-2015

01:46

x86

Clfsuninstall.mof

Not applicable

123

07-May-2014

23:47

Not applicable

For all supported x64-based versions of Windows Vista and Windows Server 2008

File name

File version

File size

Date

Time

Platform

Clfsw32.dll

6.0.6002.19331

77,824

05-Mar-2015

01:58

x64

Clfsw32.dll

6.0.6002.23639

77,824

05-Mar-2015

01:35

x64

Clfs.mof

Not applicable

3,472

18-Sep-2006

21:36

Not applicable

Clfs.sys

6.0.6002.19331

360,384

05-Mar-2015

02:14

x64

Clfsuninstall.mof

Not applicable

123

18-Sep-2006

21:36

Not applicable

Clfs.mof

Not applicable

3,472

07-May-2014

23:46

Not applicable

Clfs.sys

6.0.6002.23639

360,384

05-Mar-2015

01:51

x64

Clfsuninstall.mof

Not applicable

123

07-May-2014

23:46

Not applicable

Clfsw32.dll

6.0.6002.19331

57,344

05-Mar-2015

02:23

x86

Clfsw32.dll

6.0.6002.23639

57,344

05-Mar-2015

01:41

x86

For all supported IA-64-based versions of Windows Server 2008

File name

File version

File size

Date

Time

Platform

Clfsw32.dll

6.0.6002.19331

182,272

05-Mar-2015

01:33

IA-64

Clfsw32.dll

6.0.6002.23639

182,272

05-Mar-2015

01:12

IA-64

Clfs.mof

Not applicable

3,472

03-Jan-2008

18:57

Not applicable

Clfs.sys

6.0.6002.19331

843,192

05-Mar-2015

01:49

IA-64

Clfsuninstall.mof

Not applicable

123

03-Jan-2008

18:57

Not applicable

Clfs.mof

Not applicable

3,472

07-May-2014

23:46

Not applicable

Clfs.sys

6.0.6002.23639

843,192

05-Mar-2015

01:22

IA-64

Clfsuninstall.mof

Not applicable

123

07-May-2014

23:46

Not applicable

Clfsw32.dll

6.0.6002.19331

57,344

05-Mar-2015

02:23

x86

Clfsw32.dll

6.0.6002.23639

57,344

05-Mar-2015

01:41

x86

Windows 7 and Windows Server 2008 R2 file information

  • The files that apply to a specific product, milestone (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table:

    Version

    Product

    Milestone

    Service branch

    6.1.7601.18xxx

    Windows 7 and Windows Server 2008 R2

    SP1

    GDR

    6.1.7601.22xxx

    Windows 7 and Windows Server 2008 R2

    SP1

    LDR

  • GDR service branches contain only those fixes that are widely released to address widespread, critical issues. LDR service branches contain hotfixes in addition to widely released fixes.

Note The MANIFEST files (.manifest) and MUM files (.mum) that are installed are not listed.

For all supported x86-based versions of Windows 7

File name

File version

File size

Date

Time

Platform

Clfsw32.dll

6.1.7601.18777

58,880

04-Mar-2015

04:10

x86

Clfsw32.dll

6.1.7601.22981

58,880

04-Mar-2015

04:15

x86

Clfs.sys

6.1.7601.18777

249,784

04-Mar-2015

04:16

x86

Clfs.sys

6.1.7601.22981

249,792

04-Mar-2015

04:19

x86

For all supported x64-based versions of Windows 7 and Windows Server 2008 R2

File name

File version

File size

Date

Time

Platform

Clfsw32.dll

6.1.7601.18777

79,360

04-Mar-2015

04:41

x64

Clfsw32.dll

6.1.7601.22981

79,360

04-Mar-2015

04:33

x64

Clfs.sys

6.1.7601.18777

367,552

04-Mar-2015

04:55

x64

Clfs.sys

6.1.7601.22981

367,544

04-Mar-2015

04:37

x64

Clfsw32.dll

6.1.7601.18777

58,880

04-Mar-2015

04:10

x86

Clfsw32.dll

6.1.7601.22981

58,880

04-Mar-2015

04:15

x86

For all supported IA-64-based versions of Windows Server 2008 R2

File name

File version

File size

Date

Time

Platform

Clfsw32.dll

6.1.7601.18777

187,392

04-Mar-2015

03:38

IA-64

Clfsw32.dll

6.1.7601.22981

187,392

04-Mar-2015

03:39

IA-64

Clfs.sys

6.1.7601.18777

846,784

04-Mar-2015

03:42

IA-64

Clfs.sys

6.1.7601.22981

846,776

04-Mar-2015

03:44

IA-64

Clfsw32.dll

6.1.7601.18777

58,880

04-Mar-2015

04:10

x86

Clfsw32.dll

6.1.7601.22981

58,880

04-Mar-2015

04:15

x86

Windows 8 and Windows Server 2012 file information

  • The files that apply to a specific product, milestone (RTM,SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table:

    Version

    Product

    Milestone

    Service branch

    6.2.920 0.16 xxx

    Windows 8 and Windows Server 2012

    RTM

    GDR

    6.2.920 0.20 xxx

    Windows 8 and Windows Server 2012

    RTM

    LDR

  • GDR service branches contain only those fixes that are widely released to address widespread, critical issues. LDR service branches contain hotfixes in addition to widely released fixes.

Note The MANIFEST files (.manifest) and MUM files (.mum) that are installed are not listed.

For all supported x86-based versions of Windows 8

File name

File version

File size

Date

Time

Platform

Clfsw32.dll

6.2.9200.17291

57,856

04-Mar-2015

04:52

x86

Clfsw32.dll

6.2.9200.21408

57,856

04-Mar-2015

04:23

x86

Clfs.sys

6.2.9200.17291

256,832

04-Mar-2015

05:22

x86

Clfs.sys

6.2.9200.21408

256,832

04-Mar-2015

05:07

x86

For all supported x64-based versions of Windows 8 and Windows Server 2012

File name

File version

File size

Date

Time

Platform

Clfsw32.dll

6.2.9200.17291

74,752

04-Mar-2015

06:39

x64

Clfsw32.dll

6.2.9200.21408

74,752

04-Mar-2015

05:20

x64

Clfs.sys

6.2.9200.17291

361,280

04-Mar-2015

07:29

x64

Clfs.sys

6.2.9200.21408

361,280

04-Mar-2015

07:07

x64

Clfsw32.dll

6.2.9200.17291

57,856

04-Mar-2015

04:52

x86

Clfsw32.dll

6.2.9200.21408

57,856

04-Mar-2015

04:23

x86

Windows 8.1 and Windows Server 2012 R2 file information

For all supported x86-based versions of Windows 8.1

File name

File version

File size

Date

Time

Platform

Clfsw32.dll

6.3.9600.17719

58,880

04-Mar-2015

02:19

x86

Clfs.sys

6.3.9600.17719

279,360

04-Mar-2015

10:05

x86

For all supported x64-based versions of Windows 8.1 and Windows Server 2012 R2

File name

File version

File size

Date

Time

Platform

Clfsw32.dll

6.3.9600.17719

75,264

04-Mar-2015

03:04

x64

Clfs.sys

6.3.9600.17719

377,152

04-Mar-2015

10:25

x64

Clfsw32.dll

6.3.9600.17719

58,880

04-Mar-2015

02:19

x86


Help for installing updates: Support for Microsoft Update

Security solutions for IT professionals: TechNet Security Troubleshooting and Support

Help for protecting your Windows-based computer from viruses and malware: Virus Solution and Security Center

Local support according to your country: International Support

Need more help?

Want more options?

Explore subscription benefits, browse training courses, learn how to secure your device, and more.

Communities help you ask and answer questions, give feedback, and hear from experts with rich knowledge.

Was this information helpful?

What affected your experience?
By pressing submit, your feedback will be used to improve Microsoft products and services. Your IT admin will be able to collect this data. Privacy Statement.

Thank you for your feedback!

×