Medium6.5Microsoft Server

Medium [CVE-2021-33783] Windows SMB Information Disclosure Vulnerability

This medium-severity Microsoft Server advisory covers CVE-2021-33783 affecting Windows Server 2008 R2 Service Pack 1 (Server Core installation), Windows Server 2008 Service Pack 2 (Server Core installation), Windows Server 2012 (Server Core installation).

CVE-2021-33783 Published Jul 14, 2021Updated by vendor Aug 10, 2026

CVE-2021-33783

Affected products & platforms

Microsoft ServerWindows Server

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Summary

Windows SMB Information Disclosure Vulnerability

Affected products named by the advisory: Windows Server 2008 R2 Service Pack 1; Windows Server 2008 R2 Service Pack 1 (Server Core installation); Windows Server 2008 Service Pack 2; Windows Server 2008 Service Pack 2 (Server Core installation); and 10 more.

Affected products named by the advisory: Windows Server 2012 (Server Core installation); Windows Server 2012 R2 (Server Core installation); Windows Server 2016 (Server Core installation); Windows Server 2019 (Server Core installation); and 2 more.

Affected versions

Windows 10 Version 1507 10.0.10240.0 before 10.0.10240.19003
Windows 10 Version 1607 10.0.14393.0 before 10.0.14393.4530
Windows 10 Version 1809 10.0.17763.0 before 10.0.17763.2061
Windows 10 Version 1809 10.0.0 before 10.0.17763.2061
Windows 10 Version 1909 10.0.0 before 10.0.18363.1679
Windows 10 Version 2004 10.0.0 before 10.0.19041.1110
Windows 10 Version 20H2 10.0.0 before 10.0.19042.1110
Windows 10 Version 21H1 10.0.0 before 10.0.19043.1110
Windows 7 6.1.0 before 6.1.7601.25661
Windows 7 Service Pack 1 6.1.0 before 6.1.7601.25661
Windows 8.1 6.3.0 before 6.3.9600.20069
Windows Server 2008 R2 Service Pack 1 6.1.7601.0 before 6.1.7601.25661

Official advisory · high-confidence parse· fetched 2 hours ago·verify at source

Fixed versions

10.0.10240.19003
10.0.14393.4530
10.0.17763.2061
10.0.18363.1679
10.0.19041.1110
10.0.19042.1110
10.0.19043.1110
6.1.7601.25661
6.3.9600.20069
6.0.6003.21167
6.2.9200.23409

Official advisory · high-confidence parse· fetched 2 hours ago·verify at source

Mitigation

Upgrade to a fixed release: 10.0.10240.19003, 10.0.14393.4530, 10.0.17763.2061, 10.0.18363.1679, 10.0.19041.1110, 10.0.19042.1110. That is the remediation for this advisory.

The vendor advisory may list additional interim mitigations or workarounds not captured here — review it before change work.

Official advisory · high-confidence parse· fetched 2 hours ago·verify at source

Discussion(0)

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