CVE-2021-1640: Microsoft Windows Print Spooler Time-Of-Check Time-Of-Use Denial-of-Service Vulnerability

Published Mar 9, 2021
·
Updated

This vulnerability allows local attackers to create a denial-of-service condition on affected installations of Microsoft Windows. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the Print Spooler service. By creating a directory junction, an attacker can abuse the Print Spooler service to delete a file. An attacker can leverage this vulnerability to create a denial-of-service condition on the system.

Other sources

Windows Print Spooler Elevation of Privilege Vulnerability

Microsoft

Affected Software

61 affected componentsFixes available
Microsoft Windows 10
Microsoft Windows 10=20h2
Microsoft Windows 10=1607
Microsoft Windows 10=1803
Microsoft Windows 10=1809
Microsoft Windows 10=1909
Microsoft Windows 10=2004
Microsoft Windows 7=sp1
Microsoft Windows 8.1
Microsoft Windows RT 8.1
Microsoft Windows Server 2008=sp2
Microsoft Windows Server 2008=r2-sp1
Microsoft Windows Server 2012
Microsoft Windows Server 2012=r2
Microsoft Windows Server 2016
Microsoft Windows Server 2016=20h2
Microsoft Windows Server 2016=1909
Microsoft Windows Server 2016=2004
Microsoft Windows Server 2019
Microsoft Windows 10=20H2
Microsoft Windows
Microsoft Windows Server 2012<6.2.9200.23298
6.2.9200.23298
Microsoft Windows Server 2012 R2<6.3.9600.19968
6.3.9600.19968
Microsoft Windows Server 2008 R2<6.1.7601.24566
6.1.7601.24566
Microsoft Windows Server 2008 R2<6.1.7601.24566
6.1.7601.24566
Microsoft Windows Server 2012<6.2.9200.23298
6.2.9200.23298
Microsoft Windows RT 8.1<6.3.9600.19968
6.3.9600.19968
Microsoft Windows Server 2012 R2<6.3.9600.19968
6.3.9600.19968
Microsoft Windows Server 2008<6.0.6003.21070
6.0.6003.21070
Microsoft Windows Server 2008<6.0.6003.21070
6.0.6003.21070
Microsoft Windows 8.1 for x64-based systems<6.3.9600.19968
6.3.9600.19968
Microsoft Windows Server 2016<10.0.14393.4283
10.0.14393.4283
Microsoft Windows Server 2008<6.0.6003.21070
6.0.6003.21070
Microsoft Windows 7<6.1.7601.24566
6.1.7601.24566
Microsoft Windows 7<6.1.7601.24566
6.1.7601.24566
Microsoft Windows 8.1 for 32-bit systems<6.3.9600.19968
6.3.9600.19968
Microsoft Windows Server 2008<6.0.6003.21070
6.0.6003.21070
Microsoft Windows 10<10.0.10240.18874
10.0.10240.18874
Microsoft Windows Server=2004
10.0.19043.867
Microsoft Windows Server=20H2
10.0.19043.867
Microsoft Windows 10=20H2
10.0.19043.867
Microsoft Windows 10=2004
10.0.19043.867
Microsoft Windows 10=2004
10.0.19043.867
Microsoft Windows 10=20H2
10.0.19043.867
Microsoft Windows 10=2004
10.0.19043.867
Microsoft Windows 10=1909
10.0.18363.1440
Microsoft Windows 10=1909
10.0.18363.1440
Microsoft Windows 10<10.0.10240.18874
10.0.10240.18874
Microsoft Windows Server=1909
10.0.18363.1440
Microsoft Windows 10=1909
10.0.18363.1440
Microsoft Windows Server 2016<10.0.14393.4283
10.0.14393.4283
Microsoft Windows Server 2019<10.0.17763.1817
10.0.17763.1817
Microsoft Windows 10=1803
10.0.17134.2087
Microsoft Windows 10=1607
10.0.14393.4283
Microsoft Windows 10=1803
10.0.17134.2087
Microsoft Windows Server 2019<10.0.17763.1817
10.0.17763.1817
Microsoft Windows 10=1607
10.0.14393.4283
Microsoft Windows 10=1809
10.0.17763.1817
Microsoft Windows 10=1809
10.0.17763.1817
Microsoft Windows 10=1803
10.0.17134.2087
Microsoft Windows 10=1809
10.0.17763.1817

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 6.2.9200.23298Patch KB5000840
  2. Upgrade

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

    Fixed in 6.3.9600.19968Patch KB5000853
  3. Upgrade

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

    Fixed in 6.1.7601.24566Patch KB5000851
  4. Upgrade

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

    Fixed in 6.3.9600.19968Patch KB5000848
  5. Upgrade

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

    Fixed in 6.0.6003.21070Patch KB5000856
  6. Upgrade

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

    Fixed in 10.0.14393.4283Patch KB5000803
  7. Upgrade

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

    Fixed in 10.0.10240.18874Patch KB5000807
  8. Upgrade

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

    Fixed in 10.0.19043.867Patch KB5000802
  9. Upgrade

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

    Fixed in 10.0.18363.1440Patch KB5000808
  10. Upgrade

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

    Fixed in 10.0.17763.1817Patch KB5000822
  11. Upgrade

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

    Fixed in 10.0.17134.2087Patch KB5000809

Event History

Mar 9, 2021
CVE Published
via Microsoft·08:00 AM
Data Sourced
via Microsoft·04:00 PM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·04:00 PM
Affected Software
Updated
via Microsoft·04:00 PM
Description
Mar 10, 2021
CVE Published
via MITRE·04:27 PM
Data Sourced
via MITRE·04:27 PM
DescriptionSeverity
Mar 11, 2021
Data Sourced
via NVD·04:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Apr 29, 2021
Advisory Published
via ZDI·12:00 AM
Data Sourced
via ZDI·12:00 AM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-1640?

CVE-2021-1640 has a severity rating of important according to Microsoft, indicating a potential denial-of-service vulnerability.

2

How do I fix CVE-2021-1640?

To fix CVE-2021-1640, install the relevant security updates provided by Microsoft for your affected version of Windows.

3

What versions of Windows are affected by CVE-2021-1640?

CVE-2021-1640 affects various versions of Microsoft Windows, including Windows 10, Windows Server, and Windows 7.

4

Can CVE-2021-1640 be exploited remotely?

No, CVE-2021-1640 requires local access for exploitation, as the attacker must execute low-privileged code on the target system.

5

What is the impact of CVE-2021-1640 on my system?

CVE-2021-1640 can lead to a denial-of-service condition, potentially making the system unresponsive.

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