Cyber Resilience

CVE-2021-40450

Microsoft Windows 10 1809 ≤ 10.0.17763.2237

CISA KEVActive ExploitationEUVD Exploited
Published
13 October 2021
Modified
30 October 2025
KEV Added
25 April 2022
Patch / advisory
CVSS Score v3.1 7.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.021 80th percentile
Risk Priority 83 floored blend · peak EPSS

Summary

CVE-2021-40450 is a high-severity an unspecified weakness vulnerability in Microsoft Windows 10 1809. Its CVSS base score is 7.8 (High).

Operationally, ranked in the top 20% 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.

CVE-2021-40450 is a Win32k elevation of privilege vulnerability affecting the Win32k component in Windows. It carries a CVSS 3.1 score of 7.8 reflecting local attack vector, low complexity, low privileges required, and no user interaction, with high impact on confidentiality, integrity, and availability.

An attacker with existing local access and limited privileges can exploit the flaw to elevate rights on the target system, potentially obtaining full administrative control.

Microsoft has published security guidance for the issue via its advisory portal, and the vulnerability appears in CISA's catalog of known exploited vulnerabilities, confirming observed real-world exploitation.

EU & UK References

Vulnerability Data

Win32k Elevation of Privilege Vulnerability

CWE(s)
KEV Date Added
25 April 2022

Related Threats

CVEs Like This One

CVE-2021-31955Same product: Microsoft Windows 10 1809both on KEV
CVE-2021-34486Same product: Microsoft Windows 10 1809both on KEV
CVE-2021-36948Same product: Microsoft Windows 10 1809both on KEV
CVE-2022-21971Same product: Microsoft Windows 10 1809both on KEV
CVE-2022-21882Same product: Microsoft Windows 10 1809both on KEV
CVE-2021-41357Same product: Microsoft Windows 10 2004both on KEV
CVE-2021-33739Same product: Microsoft Windows 10 1909both on KEV
CVE-2021-28310Same product: Microsoft Windows 10 1809both on KEV
CVE-2021-1732Same product: Microsoft Windows 10 1809both on KEV
CVE-2021-41379Same product: Microsoft Windows 10 1809both on KEV

Affected Assets

microsoft
windows 10 1809
≤ 10.0.17763.2237
microsoft
windows 10 1909
≤ 10.0.18363.1854
microsoft
windows 10 2004
≤ 10.0.19041.1288
microsoft
windows 10 20h2
≤ 10.0.19042.1288
microsoft
windows 10 21h1
≤ 10.0.19043.1288
microsoft
windows 11 21h2
≤ 10.0.22000.258
microsoft
windows server 2004
≤ 10.0.19041.1288
microsoft
windows server 2019
≤ 10.0.17763.2237
microsoft
windows server 2022
≤ 10.0.20348.288
microsoft
windows server 20h2
≤ 10.0.19042.1288

Mitigating Controls

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

References