CVE & CISA-KEV Catalog

CVE-2021-31956

HIGHCISA KEVEPSS 97th pctl
7.8
CVSS v3
NVD

Description

Windows NTFS Elevation of Privilege Vulnerability

CWE-191

How to fix

Remediation Available
Windows 10Windows
Install:KB5003687Microsoft
Windows 10 Version 1607Windows
Install:KB5003638Microsoft
Windows 10 Version 1809Windows
Install:KB5003646Microsoft
Windows 10 Version 1909Windows
Install:KB5003635Microsoft
Windows 10 Version 2004Windows
Install:KB5003637Microsoft
Windows 10 Version 20H2Windows
Install:KB5003637Microsoft
Windows 10 Version 21H1Windows
Install:KB5003637Microsoft
Windows 7Windows
Install:KB5003667Microsoft
Install:KB5003694Microsoft
Windows 8.1Windows
Install:KB5003671Microsoft
Install:KB5003681Microsoft
Windows RT 8.1Windows
Install:KB5003671
Windows Server 2008Windows
Install:KB5003661Microsoft
Install:KB5003695Microsoft
Windows Server 2008 R2Windows
Install:KB5003694Microsoft
Install:KB5003667Microsoft
Windows Server 2012Windows
Install:KB5003696Microsoft
Install:KB5003697Microsoft
Windows Server 2012 (Server Core installation)Windows
Install:KB5003697Microsoft
Install:KB5003696Microsoft
Windows Server 2012 R2Windows
Install:KB5003681Microsoft
Install:KB5003671Microsoft
Windows Server 2012 R2 (Server Core installation)Windows
Install:KB5003681Microsoft
Install:KB5003671Microsoft
Windows Server 2016Windows
Install:KB5003638Microsoft
Windows Server 2016 (Server Core installation)Windows
Install:KB5003638Microsoft
Windows Server 2019Windows
Install:KB5003646Microsoft
Windows Server 2019 (Server Core installation)Windows
Install:KB5003646Microsoft
Windows Server, version 2004 (Server Core installation)Windows
Install:KB5003637Microsoft
Windows Server, version 20H2 (Server Core Installation)Windows
Install:KB5003637Microsoft

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Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorLocal
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeUnchanged

Impact

ConfidentialityHigh
IntegrityHigh
AvailabilityHigh

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Exploit Intelligence

20.27%probability of exploitation in 30 days
97thpercentile

Very high risk: more likely to be exploited than 97% of all known CVEs.

Known Exploited Vulnerability (CISA KEV)

Microsoft Windows NTFS Privilege Escalation Vulnerability

Microsoft Windows New Technology File System (NTFS) contains an unspecified vulnerability that allows attackers to escalate privileges via a specially crafted application.

Apply updates per vendor instructions.

Remediation due: 2021-11-17

References

Government Resource1

Related Vulnerabilities

Other CWE-191 vulnerabilities, ordered by exploit likelihood. View all

CVESeverityCVSSEPSSExploitedFix
CVE-2014-0497Critical9.8100%KEVFix
CVE-2020-36221High7.584%-Fix
CVE-2020-36228High7.583%-Fix
CVE-2023-31102High7.871%-Fix
CVE-2024-38063Critical9.871%-Fix
CVE-2017-14496High7.566%-Fix
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CVE-2021-31956 severity badge

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-01-13.