Cyber Resilience

CVE-2021-33771

Microsoft Windows 10 1507 ≤ 10.0.10240.19003

CISA KEVActive ExploitationEUVD Exploited
Published
14 July 2021
Modified
10 August 2026
KEV Added
03 November 2021
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 0.10 95th percentile
Risk Priority 83 floored blend · peak EPSS

Summary

CVE-2021-33771 is a high-severity an unspecified weakness vulnerability in Microsoft Windows 10 1507. Its CVSS base score is 7.8 (High).

Operationally, ranked in the top 5% 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-2021-33771 is a Windows Kernel Elevation of Privilege Vulnerability affecting the Windows kernel component. It carries a CVSS 3.1 base score of 7.8 with an attack vector of local access, low attack complexity, low privileges required, and no user interaction, resulting in high impact to confidentiality, integrity, and availability.

An attacker with local access and limited privileges can exploit the flaw to escalate privileges on the affected system, potentially obtaining full control over the Windows kernel and its resources.

Microsoft security advisories referenced at portal.msrc.microsoft.com provide guidance on available patches, while the CISA Known Exploited Vulnerabilities catalog entry confirms the issue has been observed in active exploitation.

EU & UK References

Vulnerability Data

Windows Kernel Elevation of Privilege Vulnerability

CWE(s)
KEV Date Added
03 November 2021

Related Threats

CVEs Like This One

CVE-2021-31979Same product: Microsoft Windows 10 1507both on KEV
CVE-2021-31956Same product: Microsoft Windows 10 1507both on KEV
CVE-2021-31199Same product: Microsoft Windows 10 1507both on KEV
CVE-2021-34484Same product: Microsoft Windows 10 1507both on KEV
CVE-2021-31201Same product: Microsoft Windows 10 1507both on KEV
CVE-2021-40444Same product: Microsoft Windows 10 1507both on KEV
CVE-2021-36955Same product: Microsoft Windows 10 1507both on KEV
CVE-2021-1675Same product: Microsoft Windows 10 1507both on KEV
CVE-2021-41379Same product: Microsoft Windows 10 1507both on KEV
CVE-2021-33742Same product: Microsoft Windows 10 1507both on KEV

Affected Assets

microsoft
windows 10 1507
≤ 10.0.10240.19003
microsoft
windows 10 1607
≤ 10.0.14393.4530
microsoft
windows 10 1809
≤ 10.0.17763.2061
microsoft
windows 10 1909
≤ 10.0.18363.1679
microsoft
windows 10 2004
≤ 10.0.19041.1110
microsoft
windows 10 20h2
≤ 10.0.19042.1110
microsoft
windows 10 21h1
≤ 10.0.19043.1110
microsoft
windows 8.1
all versions
microsoft
windows rt 8.1
all versions
microsoft
windows server 2004
≤ 10.0.19041.1110
+4 more product configuration(s) — see NVD for full list

Mitigating Controls

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

References