CVE-2021-40449

mediumpriority · act · 90OT risk · criticalKEV · exploitedEPSS 0.819 · 100 %ileexploit · functionalEURUUS

grimoire priorityP0 · Act now

Exploitable?

Yes · in the wild

CISA KEV · 8 exploits · functional

Likely / severe?

81.9% (100th) EPSS

CVSS 4.6 · medium

Is it mine?

74 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · fstec_bdu

added 2021-11-17remediate by 2021-12-01

required action Apply updates per vendor instructions.

EPSS · scored 2026-10-24

Microsoft Windows Win32k Privilege Escalation Vulnerability

Win32k Elevation of Privilege Vulnerability

cvss

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

8.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.6–8.8

v2.04.6mediumAV:L/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 3.9 · impact 6.4

v2.04.6mediumAV:L/AC:L/Au:N/C:P/I:P/A:P/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

v3.18.8highAV:L/AC:L/PR:L/UI:N/S:C/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-416USprimaryCWE-416US

ATT&CK techniques

ATT&CK techniques this enables or maps to.

exploits (8)

Public proof-of-concept and weaponised exploit code.

exploit/windows/local/cve_2021_40449Win32k NtGdiResetDC Use After Free Local Privilege Elevationfunctional · metasploit
BL0odz/CVE-2021-40449-NtGdiResetDC-UAFBL0odz/CVE-2021-40449-NtGdiResetDC-UAFPoC · poc_in_github
CppXL/cve-2021-40449-pocCppXL/cve-2021-40449-pocPoC · poc_in_github
KaLendsi/CVE-2021-40449-Exploitwindows 10 14393 LPEPoC · poc_in_github
Kristal-g/CVE-2021-40449_pocExploit for CVE-2021-40449PoC · poc_in_github
SamuelTulach/voidmapUsing CVE-2021-40449 to manual map kernel mode driverPoC · poc_in_github

affected products (74)

Products and version ranges known to be affected.

Microsoft Windows 10 Version 150710.0.0 → 10.0.10240.19086enisa_euvdEU
Microsoft Windows 10 Version 160710.0.0 → 10.0.14393.4704enisa_euvdEU
Microsoft Windows 10 Version 180910.0.0 → 10.0.17763.2237enisa_euvdEU
Microsoft Windows 10 Version 190910.0.0 → 10.0.18363.1854enisa_euvdEU
Microsoft Windows 10 Version 200410.0.0 → 10.0.19041.1288enisa_euvdEU
Microsoft Windows 10 Version 20H210.0.0 → 10.0.19041.1288enisa_euvdEU
Microsoft Windows 10 Version 21H110.0.0 → 10.0.19041.1288enisa_euvdEU
Microsoft Windows 11 version 21H210.0.0 → 10.0.22000.258enisa_euvdEU
Microsoft Windows 76.1.0 → 6.1.7601.25740enisa_euvdEU
Microsoft Windows 7 Service Pack 16.1.0 → 6.1.7601.25740enisa_euvdEU
Microsoft Windows 8.16.3.0 → 6.3.9600.20144enisa_euvdEU
Microsoft Windows Server 2008 R2 Service Pack 16.1.0 → 6.1.7601.25740enisa_euvdEU
Microsoft Windows Server 2008 R2 Service Pack 1 (Server Core installation)6.0.0 → 6.1.7601.25740enisa_euvdEU
Microsoft Windows Server 2008 Service Pack 26.0.0 → 6.0.6003.21251enisa_euvdEU
Microsoft Windows Server 2008 Service Pack 2 (Server Core installation)6.0.0 → 6.0.6003.21251enisa_euvdEU
Microsoft Windows Server 20126.2.0 → 6.2.9200.23490enisa_euvdEU
Microsoft Windows Server 2012 (Server Core installation)6.2.0 → 6.2.9200.23490enisa_euvdEU
Microsoft Windows Server 2012 R26.3.0 → 6.3.9600.20144enisa_euvdEU
Microsoft Windows Server 2012 R2 (Server Core installation)6.3.0 → 6.3.9600.20144enisa_euvdEU
Microsoft Windows Server 201610.0.0 → 10.0.14393.4704enisa_euvdEU

showing 20 of 74

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 2021-10-13modified 2026-06-17

related (12,094)

Related entries.

ID	severity	EPSS	exploitable	published
CVE-2026-68820US	—OT critical	0.33% (25th)	KEV	2026-08-11
Use after free in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.
CVE-2026-5281US	—OT critical	0.70% (53rd)	KEV	2026-04-01
Use after free in Dawn in Google Chrome prior to 146.0.7680.178 allowed a remote attacker who had compromised the renderer process to execute arbitrary code via a crafted HTML page…
CVE-2026-2441US	high8.8OT critical	55.0% (99th)	KEV	2026-02-13
Use after free in CSS in Google Chrome prior to 145.0.7632.75 allowed a remote attacker to execute arbitrary code inside a sandbox via a crafted HTML page. (Chromium security sever…
CVE-2025-43529US	—OT critical	8.76% (95th)	KEV	2025-12-17
A use-after-free issue was addressed with improved memory management. This issue is fixed in Safari 26.2, iOS 18.7.3 and iPadOS 18.7.3, iOS 26.2 and iPadOS 26.2, macOS Tahoe 26.2,…
CVE-2025-62221US	—OT critical	2.50% (85th)	KEV	2025-12-09
Use after free in Windows Cloud Files Mini Filter Driver allows an authorized attacker to elevate privileges locally.

+12089 more

references (11)

External citations — patches, advisories, analysis.

scry

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