CVE-2021-34491: Win32k Information Disclosure Vulnerability

Published Jul 13, 2021
·
Updated

Win32k Information Disclosure Vulnerability

Affected Software

43 affected componentsFixes available
Microsoft Windows 10
Microsoft Windows 10=20h2
Microsoft Windows 10=21h1
Microsoft Windows 10=1607
Microsoft Windows 10=1809
Microsoft Windows 10=1909
Microsoft Windows 10=2004
Microsoft Windows 8.1
Microsoft Windows RT 8.1
Microsoft Windows Server 2012=r2
Microsoft Windows Server 2016
Microsoft Windows Server 2016=20h2
Microsoft Windows Server 2016=2004
Microsoft Windows Server 2019
Microsoft Windows 8.1 for 32-bit systems<6.3.9600.20069
6.3.9600.20069
Microsoft Windows Server 2016<10.0.14393.4530
10.0.14393.4530
Microsoft Windows Server 2016<10.0.14393.4530
10.0.14393.4530
Microsoft Windows Server 2012 R2<6.3.9600.20069
6.3.9600.20069
Microsoft Windows Server 2012 R2<6.3.9600.20069
6.3.9600.20069
Microsoft Windows 10=1607
10.0.14393.4530
Microsoft Windows RT 8.1<6.3.9600.20069
6.3.9600.20069
Microsoft Windows 8.1 for x64-based systems<6.3.9600.20069
6.3.9600.20069
Microsoft Windows 10<10.0.10240.19003
10.0.10240.19003
Microsoft Windows 10=20H2
10.0.19042.1110
Microsoft Windows 10=1607
10.0.14393.4530
Microsoft Windows 10=21H1
10.0.19043.1110
Microsoft Windows 10=20H2
10.0.19042.1110
Microsoft Windows Server=20H2
10.0.19042.1110
Microsoft Windows Server=2004
10.0.19041.1110
Microsoft Windows 10=2004
10.0.19041.1110
Microsoft Windows Server 2019<10.0.17763.2061
10.0.17763.2061
Microsoft Windows 10=1909
10.0.18363.1679
Microsoft Windows 10<10.0.10240.19003
10.0.10240.19003
Microsoft Windows 10=1909
10.0.18363.1679
Microsoft Windows 10=21H1
10.0.19043.1110
Microsoft Windows 10=21H1
10.0.19043.1110
Microsoft Windows 10=1909
10.0.18363.1679
Microsoft Windows Server 2019<10.0.17763.2061
10.0.17763.2061
Microsoft Windows 10=2004
10.0.19041.1110
Microsoft Windows 10=2004
10.0.19041.1110
Microsoft Windows 10=1809
10.0.17763.2061
Microsoft Windows 10=1809
10.0.17763.2061
Microsoft Windows 10=1809
10.0.17763.2061

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 6.3.9600.20069Patch KB5004285
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.14393.4530Patch KB5004238
  3. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 6.3.9600.20069Patch KB5004298
  4. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.10240.19003Patch KB5004249
  5. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.19042.1110Patch KB5004237
  6. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.19043.1110Patch KB5004237
  7. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.19041.1110Patch KB5004237
  8. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.17763.2061Patch KB5004244
  9. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.0.18363.1679Patch KB5004245

Event History

Jul 13, 2021
CVE Published
via Microsoft·02:00 PM
Data Sourced
via Microsoft·02:00 PM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·02:00 PM
Affected Software
Updated
via Microsoft·02:00 PM
Description
Jul 14, 2021
CVE Published
via MITRE·05:54 PM
Data Sourced
via MITRE·05:54 PM
DescriptionSeverity
Data Sourced
via NVD·06:15 PM
RemedyDescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-34491?

CVE-2021-34491 has a severity rating of Important, indicating a significant risk of information disclosure.

2

How do I fix CVE-2021-34491?

The recommended fix for CVE-2021-34491 is to apply the latest security updates provided by Microsoft for affected versions of Windows.

3

Which versions of Windows are affected by CVE-2021-34491?

CVE-2021-34491 affects multiple versions, including Windows 10, Windows 8.1, and certain Windows Server editions.

4

What type of vulnerability is CVE-2021-34491?

CVE-2021-34491 is classified as a Win32k Information Disclosure Vulnerability.

5

What are the potential impacts of CVE-2021-34491?

Exploitation of CVE-2021-34491 could lead to unauthorized access to sensitive information from the operating system.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203