CVEs / CVE-2021-33739

CVE-2021-33739: Microsoft Desktop Window Manager (DWM) Core Library Privilege Escalation Vulnerability

Known exploited in the CISA KEV catalog since 3 Nov 2021
medium 4.6 CVSS 2.0 (NVD)
EPSS 6.55% chance of exploitation in the next 30 days, higher than 93% of CVEs (30 Oct 2026)
Last changed at its sources 17 Jun 2026

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Summary

Microsoft Desktop Window Manager (DWM) Core Library contains an unspecified vulnerability that allows for privilege escalation.
CISA, Known Exploited Vulnerabilities catalog

Description

Microsoft DWM Core Library Elevation of Privilege Vulnerability
The CVE record, via NVD · published 8 Jun 2021 · NVD status: Analyzed

Affected and fixed versions

As stated by the CVE record (from the CNA)
Product	Affected	Fixed in
Microsoft Windows 10 Version 1909	from 10.0.0, before 10.0.18363.1621	10.0.18363.1621
Microsoft Windows 10 Version 21H1	from 10.0.0, before 10.0.19043.1052	10.0.19043.1052
Microsoft Windows 10 Version 2004	from 10.0.0, before 10.0.19041.1052	10.0.19041.1052
Microsoft Windows Server version 2004	from 10.0.0, before 10.0.19041.1052	10.0.19041.1052
Microsoft Windows 10 Version 20H2	from 10.0.0, before 10.0.19042.1052	10.0.19042.1052
Microsoft Windows Server version 20H2	from 10.0.0, before 10.0.19042.1052	10.0.19042.1052

Exploitation

In CISA KEV since	3 Nov 2021
Due date for US federal agencies	17 Nov 2021
Used in ransomware campaigns	Unknown
Required action	Apply updates per vendor instructions.

Severity

CVSS 2.0	4.6 medium `AV:L/AC:L/Au:N/C:P/I:P/A:P` Scored by NVD

References

CVE-2021-33739 on NVD
CVE-2021-33739 in the CISA KEV catalog
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-33739 Patch, Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-33739 US Government Resource

Sources

Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.

This product uses data from the NVD API but is not endorsed or certified by the NVD.