CVE-2021-33786: Windows LSA Security Feature Bypass Vulnerability

Published Jul 13, 2021
·
Updated

Windows LSA Security Feature Bypass Vulnerability

Affected Software

24 affected componentsFixes available
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=2004
Microsoft Windows Server 2019
Microsoft Windows Server 2008 R2<6.1.7601.25661
6.1.7601.25661
Microsoft Windows Server 2008 R2<6.1.7601.25661
6.1.7601.25661
Microsoft Windows Server 2012 R2<6.3.9600.20069
6.3.9600.20069
Microsoft Windows Server 2008<6.0.6003.21167
6.0.6003.21167
Microsoft Windows Server 2012<6.2.9200.23409
6.2.9200.23409
Microsoft Windows Server 2012 R2<6.3.9600.20069
6.3.9600.20069
Microsoft Windows Server 2008<6.0.6003.21167
6.0.6003.21167
Microsoft Windows Server 2012<6.2.9200.23409
6.2.9200.23409
Microsoft Windows Server 2008<6.0.6003.21167
6.0.6003.21167
Microsoft Windows Server 2008<6.0.6003.21167
6.0.6003.21167
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=20H2
10.0.19042.1110
Microsoft Windows Server 2019<10.0.17763.2061
10.0.17763.2061
Microsoft Windows Server 2019<10.0.17763.2061
10.0.17763.2061
Microsoft Windows Server=2004
10.0.19041.1110

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 6.1.7601.25661Patch KB5004307
  2. Upgrade

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

    Fixed in 6.3.9600.20069Patch KB5004285
  3. Upgrade

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

    Fixed in 6.2.9200.23409Patch KB5004302
  4. Upgrade

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

    Fixed in 6.0.6003.21167Patch KB5004299
  5. Upgrade

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

    Fixed in 10.0.14393.4530Patch KB5004238
  6. Upgrade

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

    Fixed in 10.0.19042.1110Patch KB5004237
  7. Upgrade

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

    Fixed in 10.0.17763.2061Patch KB5004244
  8. Upgrade

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

    Fixed in 10.0.19041.1110Patch KB5004237

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·05:53 PM
Data Sourced
via MITRE·05:53 PM
DescriptionSeverity
Data Sourced
via NVD·06:15 PM
RemedyDescriptionSeverityAffected Software

Frequently Asked Questions

1

What level of access does an attacker need to exploit this vulnerability?

The CVSS vector indicates that an attacker needs low-level privileges on the affected system. Exploitation does not require user interaction and can be performed over the network.

2

What is the potential impact if exploitation succeeds?

Successful exploitation can result in high impacts to confidentiality and integrity. The CVSS vector does not indicate an availability impact.

3

Which Windows Server versions are listed as affected?

The listed affected products are Windows Server 2008, 2008 R2, 2012, 2012 R2, 2016, and 2019, along with a general Microsoft Windows Server entry.

Contact

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