vulntracker.iovulntracker.io
© 2026 vulntracker.io

CVE-2021-40449

Win32k Elevation of Privilege Vulnerability

HIGH
7.8
CVSS Score
Published: October 13, 2021 at 12:26 AM UTC
Updated: June 17, 2026 at 04:06 AM UTC
19 products affected across 1 vendorWindows Server 2016Windows Server 2019Windows Server 2012

Using Windows 10 Version 1809 by Microsoft?

Get instant alerts when new vulnerabilities affect Windows 10 Version 1809 - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Start FreeSign In
Severity
HIGH7.8
Exploitation
CISA KEV
Exploit prediction
EPSS 82%
SSVC
Active

Actively Exploited

CISA Known Exploited Vulnerabilities (KEV) Catalog

EPSS Score81.9%

EPSS (Exploit Prediction Scoring System) estimates a 81.9% chance this CVE is exploited in the wild within the next 30 days — higher than 100% of all CVEs. It complements CVSS: a high EPSS on a mid-severity CVE can still be urgent.

Unspecified vulnerability allows for an authenticated user to escalate privileges.

Required Action
Apply updates per vendor instructions.
Ransomware Use
Known
Added to KEV
Nov 17, 2021
Remediation Due
Dec 1, 2021
1793 days overdue
Notes
https://nvd.nist.gov/vuln/detail/CVE-2021-40449

Description

Win32k Elevation of Privilege Vulnerability

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Windows 10 1507· Microsoft
95%
v < 10.0.10240.1908610.0.0 ≤ v < 10.0.10240.1908610.0.010.0.10240.19086
Affected range stops below 10.0.10240.19086, so it looks safe — our inference, not a vendor statement
Windows 10 1607· Microsoft
95%
v < 10.0.14393.470410.0.0 ≤ v < 10.0.14393.470410.0.010.0.14393.4704
Affected range stops below 10.0.14393.4704, so it looks safe — our inference, not a vendor statement
Windows 10 1809· Microsoft
95%
v < 10.0.17763.223710.0.0 ≤ v < 10.0.17763.223710.0.010.0.17763.223710.0.18363.185410.0.19041.1288
Affected range stops below 10.0.17763.2237, so it looks safe — our inference, not a vendor statement
Windows 10 1909· Microsoft
95%
v < 10.0.18363.185410.0.0 ≤ v < 10.0.18363.185410.0.010.0.18363.1854
Affected range stops below 10.0.18363.1854, so it looks safe — our inference, not a vendor statement
Windows 10 2004· Microsoft
95%
v < 10.0.19041.128810.0.0 ≤ v < 10.0.19041.128810.0.0
Affected range stops below 10.0.19041.1288, so it looks safe — our inference, not a vendor statement
Windows 10 20H2· Microsoft
95%
v < 10.0.19041.128810.0.0 ≤ v < 10.0.19041.128810.0.0
Affected range stops below 10.0.19041.1288, so it looks safe — our inference, not a vendor statement
Windows 10 21H1· Microsoft
95%
v < 10.0.19041.128810.0.0 ≤ v < 10.0.19041.128810.0.0
Affected range stops below 10.0.19041.1288, so it looks safe — our inference, not a vendor statement
Windows 11· Microsoft
95%
All versions
Windows 11 21H2· Microsoft
95%
v < 10.0.22000.25810.0.0 ≤ v < 10.0.22000.25810.0.0
Affected range stops below 10.0.22000.258, so it looks safe — our inference, not a vendor statement
Windows 7· Microsoft
95%
6.1.0 ≤ v < 6.1.7601.257406.1.06.1.7601.25740sp1
Affected range stops below 6.1.7601.25740, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

References (3)

x_refsource_MISCExploitThird Party AdvisoryVDB Entry
Source: [email protected]
http://packetstormsecurity.com/files/164926/Win32k-NtGdiResetDC-Use-After-Free-Local-Privilege-Escalation.html
x_refsource_MISCPatchVendor Advisory
Source: [email protected]
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-40449
US Government Resource
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-40449

SSVC — Action Prioritization

SSVCActiveNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.8HIGHmicrosoft
Vector?

Quick Info

StatusANALYZED
CWE
CWE-416

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Create accountSign in
Free plan, no card