CVE-2021-31956

highpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.223 · 98 %ileexploit · PoCEURUUS

grimoire priorityP0 · Act now

Exploitable?

Yes · in the wild

CISA KEV · 6 exploits · PoC

Likely / severe?

22.3% (98th) EPSS

CVSS 9.3 · high

Is it mine?

69 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · fstec_bdu

added 2021-11-03remediate by 2021-11-17

required action Apply updates per vendor instructions.

EPSS · scored 2026-10-22

Microsoft Windows NTFS Privilege Escalation Vulnerability

Windows NTFS Elevation of Privilege Vulnerability

cvss

Technical severity, 0–10. One row per scoring source.

9.3

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.09.3highAV:N/AC:M/Au:N/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 8.6 · impact 10

v2.09.3highAV:N/AC:M/Au:N/C:C/I:C/A:C/E:Hsecondary · CVSS-BT (t0sche)

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · NVD / NIST USexploitability 1.8 · impact 5.9

v3.17.8highAV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:Csecondary · ENISA EU

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · secure@microsoft.com USexploitability 1.8 · impact 5.9

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: active · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-191USprimaryCWE-119USCWE-264US

exploits (6)

Public proof-of-concept and weaponised exploit code.

DaoshuReal/UAC-Elevation-CVEfodhelper-based UAC bypass poc for CVE-2021-31956, registry keys to SYSTEM without a prompt. educationalPoC · poc_in_github
Y3A/CVE-2021-31956Win10 20H2 LPE for CVE-2021-31956PoC · poc_in_github
aazhuliang/CVE-2021-31956-EXPaazhuliang/CVE-2021-31956-EXPPoC · poc_in_github
deletehead/Pool-Overflow-CVE-2021-31956Kernel Pool Overflow Exploit targeting CVE-2021-31956PoC · poc_in_github
hoangprod/CVE-2021-31956-POChoangprod/CVE-2021-31956-POCPoC · poc_in_github
hzshang/CVE-2021-31956hzshang/CVE-2021-31956PoC · poc_in_github

affected products (69)

Products and version ranges known to be affected.

Microsoft Windows 10 Version 150710.0.0 → 10.0.10240.18967enisa_euvdEU
Microsoft Windows 10 Version 160710.0.0 → 10.0.14393.4467enisa_euvdEU
Microsoft Windows 10 Version 180910.0.0 → 10.0.17763.1999enisa_euvdEU
Microsoft Windows 10 Version 190910.0.0 → 10.0.18363.1621enisa_euvdEU
Microsoft Windows 10 Version 200410.0.0 → 10.0.19041.1052enisa_euvdEU
Microsoft Windows 10 Version 20H210.0.0 → 10.0.19042.1052enisa_euvdEU
Microsoft Windows 10 Version 21H110.0.0 → 10.0.19043.1052enisa_euvdEU
Microsoft Windows 76.1.0 → 6.1.7601.25632enisa_euvdEU
Microsoft Windows 7 Service Pack 16.1.0 → 6.1.7601.25632enisa_euvdEU
Microsoft Windows 8.16.3.0 → 6.3.9600.20044enisa_euvdEU
Microsoft Windows 8.16.3.0 → 6.3.9600.20045enisa_euvdEU
Microsoft Windows Server 2008 R2 Service Pack 16.1.0 → 6.1.7601.25632enisa_euvdEU
Microsoft Windows Server 2008 R2 Service Pack 1 (Server Core installation)6.0.0 → 6.1.7601.25632enisa_euvdEU
Microsoft Windows Server 2008 Service Pack 26.0.0 → 6.0.6003.21137enisa_euvdEU
Microsoft Windows Server 2008 Service Pack 2 (Server Core installation)6.0.0 → 6.0.6003.21137enisa_euvdEU
Microsoft Windows Server 20126.2.0 → 6.2.9200.23372enisa_euvdEU
Microsoft Windows Server 2012 (Server Core installation)6.2.0 → 6.2.9200.23372enisa_euvdEU
Microsoft Windows Server 2012 R26.3.0 → 6.3.9600.20044enisa_euvdEU
Microsoft Windows Server 2012 R26.3.0 → 6.3.9600.20045enisa_euvdEU
Microsoft Windows Server 2012 R2 (Server Core installation)6.3.0 → 6.3.9600.20044enisa_euvdEU

showing 20 of 69

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu NVD CVE.org MITRE

published 2021-06-08modified 2026-06-17

related (716)

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+711 more

references (7)

External citations — patches, advisories, analysis.

scry

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