Cyber Resilience

CVE-2021-33739

Microsoft Windows 10 1909 ≤ 10.0.18363.1621

CISA KEVActive ExploitationEUVD Exploited
Published
08 June 2021
Modified
30 October 2025
KEV Added
03 November 2021
Patch / advisory
CVSS Score v3.1 8.4
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.066 93th percentile
Risk Priority 88 floored blend · peak EPSS

Summary

CVE-2021-33739 is a high-severity an unspecified weakness vulnerability in Microsoft Windows 10 1909. Its CVSS base score is 8.4 (High).

Operationally, ranked in the top 7% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

The vulnerability CVE-2021-33739 is an elevation of privilege flaw in the Microsoft DWM Core Library. It carries a CVSS 3.1 score of 8.4 and affects this core Windows component responsible for desktop window management.

A local attacker with no privileges or user interaction required can exploit the issue to obtain full control over confidentiality, integrity, and availability on the target system. The attack vector is local and the scope remains unchanged.

Microsoft security advisories at the referenced MSRC portal URLs describe available patches, while the CISA known exploited vulnerabilities catalog entry confirms active real-world exploitation and recommends prompt remediation through updates.

EU & UK References

Vulnerability Data

Microsoft DWM Core Library Elevation of Privilege Vulnerability

CWE(s)
KEV Date Added
03 November 2021

Related Threats

CVEs Like This One

CVE-2021-31955Same product: Microsoft Windows 10 1909both on KEV
CVE-2021-34486Same product: Microsoft Windows 10 1909both on KEV
CVE-2021-36948Same product: Microsoft Windows 10 1909both on KEV
CVE-2021-31166Same product: Microsoft Windows 10 2004both on KEV
CVE-2021-41357Same product: Microsoft Windows 10 2004both on KEV
CVE-2021-40450Same product: Microsoft Windows 10 1909both on KEV
CVE-2021-36934Same product: Microsoft Windows 10 1909both on KEV
CVE-2021-28310Same product: Microsoft Windows 10 1909both on KEV
CVE-2021-1732Same product: Microsoft Windows 10 1909both on KEV
CVE-2021-33771Same product: Microsoft Windows 10 1909both on KEV

Affected Assets

microsoft
windows 10 1909
≤ 10.0.18363.1621
microsoft
windows 10 2004
≤ 10.0.19041.1052
microsoft
windows 10 20h2
≤ 10.0.19042.1052
microsoft
windows 10 21h1
≤ 10.0.19043.1052
microsoft
windows server 2004
≤ 10.0.19041.1052
microsoft
windows server 20h2
≤ 10.0.19042.1052

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References