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Evidence dossier
CVE-2021-40449
Win32k Elevation of Privilege Vulnerability
68.6–91.6Priority evidence range
gen-56ccdaf9Normalized restatement
Win32k Elevation of Privilege Vulnerability
- State
- PUBLISHED
- Published
- Oct 13, 2021
- Updated
- Oct 21, 2025
- Evidence coverage
- 72%
2026-07-18 · v2026.06.15 · percentile 99.4%
Distinct CVSS assessments remain side by side; none are averaged.
Source comparison
Who said what
microsoftoriginal assertion
container
Win32k Elevation of Privilege Vulnerability
Jul 19, 2026Original evidence ↗
CISA KEVoriginal assertion
observed_exploitation
Microsoft Windows Win32k Privilege Escalation Vulnerability
Jul 19, 2026Original evidence ↗
FIRST EPSSoriginal assertion
model_probability
Probability 0.733810000000; percentile 0.994030000000
Jul 19, 2026Original evidence ↗
Applicability
Cited product scope
MicrosoftWindows 10 Version 1507
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.10240.19086", "versionType": "custom"}]unknownMicrosoftWindows 10 Version 1607
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.14393.4704", "versionType": "custom"}]unknownMicrosoftWindows 10 Version 1809
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.17763.2237", "versionType": "custom"}]unknownMicrosoftWindows 10 Version 1909
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.18363.1854", "versionType": "custom"}]unknownMicrosoftWindows 10 Version 2004
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.19041.1288", "versionType": "custom"}]unknownMicrosoftWindows 10 Version 20H2
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.19041.1288", "versionType": "custom"}]unknownMicrosoftWindows 10 Version 21H1
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.19041.1288", "versionType": "custom"}]unknownMicrosoftWindows 11 version 21H2
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.22000.258", "versionType": "custom"}]unknownMicrosoftWindows 7
[{"status": "affected", "version": "6.1.0", "lessThan": "6.1.7601.25740", "versionType": "custom"}]unknownMicrosoftWindows 7 Service Pack 1
[{"status": "affected", "version": "6.1.0", "lessThan": "6.1.7601.25740", "versionType": "custom"}]unknownMicrosoftWindows 8.1
[{"status": "affected", "version": "6.3.0", "lessThan": "6.3.9600.20144", "versionType": "custom"}]unknownMicrosoftWindows Server 2008 R2 Service Pack 1
[{"status": "affected", "version": "6.1.0", "lessThan": "6.1.7601.25740", "versionType": "custom"}]unknownMicrosoftWindows Server 2008 R2 Service Pack 1 (Server Core installation)
[{"status": "affected", "version": "6.0.0", "lessThan": "6.1.7601.25740", "versionType": "custom"}]unknownMicrosoftWindows Server 2008 Service Pack 2
[{"status": "affected", "version": "6.0.0", "lessThan": "6.0.6003.21251", "versionType": "custom"}]unknownMicrosoftWindows Server 2008 Service Pack 2
[{"status": "affected", "version": "6.0.0", "lessThan": "6.0.6003.21251", "versionType": "custom"}]unknownMicrosoftWindows Server 2008 Service Pack 2 (Server Core installation)
[{"status": "affected", "version": "6.0.0", "lessThan": "6.0.6003.21251", "versionType": "custom"}]unknownMicrosoftWindows Server 2012
[{"status": "affected", "version": "6.2.0", "lessThan": "6.2.9200.23490", "versionType": "custom"}]unknownMicrosoftWindows Server 2012 R2
[{"status": "affected", "version": "6.3.0", "lessThan": "6.3.9600.20144", "versionType": "custom"}]unknownMicrosoftWindows Server 2012 R2 (Server Core installation)
[{"status": "affected", "version": "6.3.0", "lessThan": "6.3.9600.20144", "versionType": "custom"}]unknownMicrosoftWindows Server 2012 (Server Core installation)
[{"status": "affected", "version": "6.2.0", "lessThan": "6.2.9200.23490", "versionType": "custom"}]unknownMicrosoftWindows Server 2016
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.14393.4704", "versionType": "custom"}]unknownMicrosoftWindows Server 2016 (Server Core installation)
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.14393.4704", "versionType": "custom"}]unknownMicrosoftWindows Server 2019
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.17763.2237", "versionType": "custom"}]unknownMicrosoftWindows Server 2019 (Server Core installation)
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.17763.2237", "versionType": "custom"}]unknownMicrosoftWindows Server 2022
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.20348.288", "versionType": "custom"}]unknownMicrosoftWindows Server version 2004
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.19041.1288", "versionType": "custom"}]unknownMicrosoftWindows Server version 20H2
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.19042.1288", "versionType": "custom"}]unknownUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_10_1507:*:*:*:*:*:*:*:*; end excluding 10.0.10240.19086supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:*:*; end excluding 10.0.14393.4704supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:*:*; end excluding 10.0.17763.2237supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_10_1909:*:*:*:*:*:*:*:*; end excluding 10.0.18363.1854supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_10_2004:*:*:*:*:*:*:*:*; end excluding 10.0.19041.1288supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_10_20h2:*:*:*:*:*:*:*:*; end excluding 10.0.19041.1288supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_10_21h1:*:*:*:*:*:*:*:*; end excluding 10.0.19041.1288supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_11:*:*:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_11_21h2:*:*:*:*:*:*:*:*; end excluding 10.0.22000.258supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_7:-:sp1:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_8.1:-:*:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_rt_8.1:-:*:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_server_2004:*:*:*:*:*:*:*:*; end excluding 10.0.19041.1288supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:*supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:*; end excluding 10.0.14393.4704supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*; end excluding 10.0.17763.2237supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*; end excluding 10.0.20348.288supportedUnknown vendorUnknown product
cpe:2.3:o:microsoft:windows_server_20h2:*:*:*:*:*:*:*:*; end excluding 10.0.19042.1288supportedAssessments
CVSS by origin
nvd@nist.govCVSS 2.0 · role Primary
AV:L/AC:L/Au:N/C:P/I:P/A:Pnvd@nist.govCVSS 3.1 · role Secondary
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecure@microsoft.comCVSS 3.1 · role Secondary
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HmicrosoftCVSS 3.1 · role unknown
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:CLimitations and unknowns
- KEV membership is authoritative for the catalog, not proof of exposure in any environment.
- EPSS is a dated model probability and not an individual-environment prediction.
- Affected or fixed status applies only to the exact cited product and version scope; unresolved scope remains unknown.
- NVD-carried upstream facts remain derivative and are not independent corroboration.
- Only NVD metrics validated under the generation-bound calculator are Public Priority eligible; direct CVE record metrics remain display-only.
- NVD CVSS source eligibility is closed: NVD-authored, exact record-source, or registered same-CVE container origin; unmapped sources remain display-only.
- Factor D is unknown in Public Core because no accepted canonical mapping-obligation ledger is present.
- Core replay supports the active and immediately prior generation; retrospective valid-at replay is deferred.