CASCACascade Atlas

Evidence dossier

CVE-2021-31955

Windows Kernel Information Disclosure Vulnerability

63.3–86.8Priority evidence range
As known Jul 19, 2026, 5:00 AM UTCgen-56ccdaf9

Normalized restatement

Windows Kernel Information Disclosure Vulnerability

State
PUBLISHED
Published
Jun 8, 2021
Updated
Oct 21, 2025
Evidence coverage
72%
CISA KEVCatalog member

Apply updates per vendor instructions.

FIRST EPSS81.11%

2026-07-18 · v2026.06.15 · percentile 99.6%

Source stateConflict visible

Distinct CVSS assessments remain side by side; none are averaged.

Source comparison

Who said what

CISA-ADPindependent enrichment
container

CISA ADP Vulnrichment

CVEderivative copy
container

CVE Program Container

microsoftoriginal assertion
container

Windows Kernel Information Disclosure Vulnerability

CISA KEVoriginal assertion
observed_exploitation

Microsoft Windows Kernel Information Disclosure Vulnerability

FIRST EPSSoriginal assertion
model_probability

Probability 0.811070000000; percentile 0.995930000000

Applicability

Cited product scope

Trace impact →
MicrosoftWindows 10 Version 1809
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.17763.1999", "versionType": "custom"}]unknown
MicrosoftWindows 10 Version 1909
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.18363.1621", "versionType": "custom"}]unknown
MicrosoftWindows 10 Version 2004
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.19041.1052", "versionType": "custom"}]unknown
MicrosoftWindows 10 Version 20H2
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.19042.1052", "versionType": "custom"}]unknown
MicrosoftWindows 10 Version 21H1
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.19043.1052", "versionType": "custom"}]unknown
MicrosoftWindows Server 2019
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.17763.1999", "versionType": "custom"}]unknown
MicrosoftWindows Server 2019 (Server Core installation)
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.17763.1999", "versionType": "custom"}]unknown
MicrosoftWindows Server version 2004
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.19041.1052", "versionType": "custom"}]unknown
MicrosoftWindows Server version 20H2
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.19042.1052", "versionType": "custom"}]unknown
Unknown vendorUnknown product
cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:*:*; end excluding 10.0.17763.1999supported
Unknown vendorUnknown product
cpe:2.3:o:microsoft:windows_10_1909:*:*:*:*:*:*:*:*; end excluding 10.0.18363.1621supported
Unknown vendorUnknown product
cpe:2.3:o:microsoft:windows_10_2004:*:*:*:*:*:*:*:*; end excluding 10.0.19041.1052supported
Unknown vendorUnknown product
cpe:2.3:o:microsoft:windows_10_20h2:*:*:*:*:*:*:*:*; end excluding 10.0.19042.1052supported
Unknown vendorUnknown product
cpe:2.3:o:microsoft:windows_10_21h1:*:*:*:*:*:*:*:*; end excluding 10.0.19043.1052supported
Unknown vendorUnknown product
cpe:2.3:o:microsoft:windows_server_2004:*:*:*:*:*:*:*:*; end excluding 10.0.19041.1052supported
Unknown vendorUnknown product
cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*; end excluding 10.0.17763.1999supported
Unknown vendorUnknown product
cpe:2.3:o:microsoft:windows_server_20h2:*:*:*:*:*:*:*:*; end excluding 10.0.19042.1052supported

Assessments

CVSS by origin

2.1
nvd@nist.govCVSS 2.0 · role PrimaryAV:L/AC:L/Au:N/C:P/I:N/A:N
5.5
nvd@nist.govCVSS 3.1 · role SecondaryCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
5.5
secure@microsoft.comCVSS 3.1 · role SecondaryCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
5.5
microsoftCVSS 3.1 · role unknownCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:F/RL:O/RC:C

Limitations 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.