Evidence dossier

CVE-2024-21338

Windows Kernel Elevation of Privilege Vulnerability

Exploited in the wild (CISA KEV since Mar 4, 2024). microsoft reports CVSS 3.1 7.8. EPSS estimates 59.8% exploit likelihood as of Aug 27, 2026.

75.086.7Priority evidence range
Evidence current through Aug 27, 2026, 6:09 PM UTC

As of Aug 27, 2026

Normalized restatement

Windows Kernel Elevation of Privilege Vulnerability

State
PUBLISHED
Published
Feb 13, 2024
Updated
Jul 31, 2026
Evidence coverage
85%

Evidence chronology

What was known when

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  1. Source dateFirst observed by CASCA
    CISA KEV

    Exploitation cataloged: Microsoft Windows Kernel Exposed IOCTL with Insufficient Access Control Vulnerability

    Inspect raw assertion
    Field
    observed_exploitation
    Value
    Microsoft Windows Kernel Exposed IOCTL with Insufficient Access Control Vulnerability
    Original evidence ↗
  2. Source dateSource date omittedFirst observed by CASCA
    CISA-ADP

    Record text: CISA ADP Vulnrichment

    Inspect raw assertion
    Field
    container
    Value
    CISA ADP Vulnrichment
    Original evidence ↗
  3. Source dateSource date omittedFirst observed by CASCA
    CVE Program

    Record text: CVE Program Container

    Inspect raw assertion
    Field
    container
    Value
    CVE Program Container
    Original evidence ↗
  4. Source dateSource date omittedFirst observed by CASCA
    microsoft

    Record text: Windows Kernel Elevation of Privilege Vulnerability

    Inspect raw assertion
    Field
    container
    Value
    Windows Kernel Elevation of Privilege Vulnerability
    Original evidence ↗
  5. Source dateFirst observed by CASCA
    FIRST EPSS

    EPSS score: 59.81% probability · 99.06th percentile

    Inspect raw assertion
    Field
    model_probability
    Value
    Probability 0.598100000000; percentile 0.990610000000
    Original evidence ↗
ExploitationCatalog member

CISA KEV · catalog date Mar 4, 2024 · first observed Jul 19, 2026

Exploit likelihood59.81%

FIRST EPSS · score date Aug 27, 2026 · 99.1th percentile · first observed Aug 27, 2026

SeverityCVSS 7.8

microsoft · CVSS 3.1 · first observed Aug 1, 2026 · same-version scores align in this snapshot

Evidence detail

Source limits and decisions

Why each evidence state has this value

casca-unknown-reasons-v1
Exploitation statusEvidence supported

Eligible evidence is present for this bounded claim.

Revision
evidence-policy-v1.1.0
Cutoff
Aug 27, 2026
Resolution
None
Exploit likelihoodEvidence supported

Eligible evidence is present for this bounded claim.

Revision
evidence-policy-v1.1.0
Cutoff
Aug 27, 2026
Resolution
None
Severity assessmentEvidence supported

Eligible evidence is present for this bounded claim.

Revision
casca-direct-cvss-eligibility-v1
Cutoff
Aug 27, 2026
Resolution
None
Affected productsSource-reported scope

The cited source assertion is retained while canonical product linkage remains open.

Revision
casca-factor-d-obligations-v1
Cutoff
Aug 27, 2026
Resolution
Resolve identity

Source comparison

Who said what

CISA KEVOriginal assertion
Exploitation cataloged

Microsoft Windows Kernel Exposed IOCTL with Insufficient Access Control Vulnerability

Inspect raw assertion
Field
observed_exploitation
Value
Microsoft Windows Kernel Exposed IOCTL with Insufficient Access Control Vulnerability
Source dateFirst observed by CASCAOriginal evidence ↗
CISA-ADPIndependent enrichment
Record text

CISA ADP Vulnrichment

Inspect raw assertion
Field
container
Value
CISA ADP Vulnrichment
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
CVE ProgramDerivative copy
Record text

CVE Program Container

Inspect raw assertion
Field
container
Value
CVE Program Container
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
microsoftOriginal assertion
Record text

Windows Kernel Elevation of Privilege Vulnerability

Inspect raw assertion
Field
container
Value
Windows Kernel Elevation of Privilege Vulnerability
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
FIRST EPSSOriginal assertion
EPSS score

59.81% probability · 99.06th percentile

Inspect raw assertion
Field
model_probability
Value
Probability 0.598100000000; percentile 0.990610000000
Source dateFirst observed by CASCAOriginal evidence ↗

Applicability

Cited product scope

Trace impact →
9Underlying assertions
9Canonical products
9Target assertions
0Constraint assertions

Grouped from 1 configuration nodes in this exact snapshot. Visual grouping is navigational; asset exposure and root cause require cited evidence.

Identity source boundaries
  • Cpe dictionary1,775,266 records · observed through 2026-07-21T06:45:29.809Z27d65b0f-b718-4b4f-bb79-c47c68d09dfa
  • Cpe match643,502 records · observed through 2026-07-21T08:13:17.697Z955dae73-7302-438b-aee1-058d7cc5d48e

21 scope groups

microsoft · source assertedMicrosoftWindows 10 Version 1809Direct source scope
Affected: 10.0.17763.0 to before 10.0.17763.5458 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "10.0.17763.0", "lessThan": "10.0.17763.5458", "versionType": "custom"}]
microsoft · source assertedMicrosoftWindows 10 Version 1809Direct source scope
Affected: 10.0.0 to before 10.0.17763.5458 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.17763.5458", "versionType": "custom"}]
microsoft · source assertedMicrosoftWindows 10 Version 21H2Direct source scope
Affected: 10.0.19043.0 to before 10.0.19044.4046 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "10.0.19043.0", "lessThan": "10.0.19044.4046", "versionType": "custom"}]
microsoft · source assertedMicrosoftWindows 10 Version 22H2Direct source scope
Affected: 10.0.19045.0 to before 10.0.19045.4046 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "10.0.19045.0", "lessThan": "10.0.19045.4046", "versionType": "custom"}]
microsoft · source assertedMicrosoftWindows 11 version 21H2Direct source scope
Affected: 10.0.0 to before 10.0.22000.2777 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.22000.2777", "versionType": "custom"}]
microsoft · source assertedMicrosoftWindows 11 version 22H2Direct source scope
Affected: 10.0.22621.0 to before 10.0.22621.3155 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "10.0.22621.0", "lessThan": "10.0.22621.3155", "versionType": "custom"}]
microsoft · source assertedMicrosoftWindows 11 version 22H3Direct source scope
Affected: 10.0.22631.0 to before 10.0.22631.3155 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "10.0.22631.0", "lessThan": "10.0.22631.3155", "versionType": "custom"}]
microsoft · source assertedMicrosoftWindows 11 Version 23H2Direct source scope
Affected: 10.0.22631.0 to before 10.0.22631.3155 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "10.0.22631.0", "lessThan": "10.0.22631.3155", "versionType": "custom"}]
microsoft · source assertedMicrosoftWindows Server 2019Direct source scope
Affected: 10.0.17763.0 to before 10.0.17763.5458 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "10.0.17763.0", "lessThan": "10.0.17763.5458", "versionType": "custom"}]
microsoft · source assertedMicrosoftWindows Server 2019 (Server Core installation)Direct source scope
Affected: 10.0.17763.0 to before 10.0.17763.5458 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "10.0.17763.0", "lessThan": "10.0.17763.5458", "versionType": "custom"}]
microsoft · source assertedMicrosoftWindows Server 2022Direct source scope
Affected: 10.0.20348.0 to before 10.0.20348.2322 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "10.0.20348.0", "lessThan": "10.0.20348.2322", "versionType": "custom"}]
microsoft · source assertedMicrosoftWindows Server 2022, 23H2 Edition (Server Core installation)Direct source scope
Affected: 10.0.25398.0 to before 10.0.25398.709 (custom comparison)
Source-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Inspect raw assertion[{"status": "affected", "version": "10.0.25398.0", "lessThan": "10.0.25398.709", "versionType": "custom"}]
NVD CPE · OPERATING SYSTEMmicrosoftwindows_10_1809Vulnerable target · 1 assertions
Any version (unconstrained) (< 10.0.17763.5458)Canonical identity product-a3084138383423221f61594e86f5b295e5e254acd7ae5284f45e0877a084db43Linked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 0
    Logic
    OR
    Version bounds
    through excluding 10.0.17763.5458
    Match ID
    a1689dfd-d52d-4121-bfd7-dbf2be4e7de8
NVD CPE · OPERATING SYSTEMmicrosoftwindows_10_21h2Vulnerable target · 1 assertions
Any version (unconstrained) (< 10.0.19044.4046)Canonical identity product-ec10c9f400f23fdf118887f60fe116ffde4adb76dcf118cdd3a7556fd033da3bLinked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 1
    Logic
    OR
    Version bounds
    through excluding 10.0.19044.4046
    Match ID
    c78776cc-3a9c-41a3-8beb-d71d92f6579d
NVD CPE · OPERATING SYSTEMmicrosoftwindows_10_22h2Vulnerable target · 1 assertions
Any version (unconstrained) (< 10.0.19045.4046)Canonical identity product-a6295b9daad3ca57ce70751badba5b7fe99229c8a562cc7400e8cfef3daccaeeLinked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 2
    Logic
    OR
    Version bounds
    through excluding 10.0.19045.4046
    Match ID
    806ca6d2-42b2-4244-a5ed-d23e6dd56772
NVD CPE · OPERATING SYSTEMmicrosoftwindows_11_21h2Vulnerable target · 1 assertions
Any version (unconstrained) (< 10.0.22000.2777)Canonical identity product-7fe28b5b5b17e017d9554204df059dd619746ffb5c80da87bcbfb1c52720d2f4Linked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:microsoft:windows_11_21h2:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 3
    Logic
    OR
    Version bounds
    through excluding 10.0.22000.2777
    Match ID
    3f7f8173-9e59-48e4-98c9-4beb6ae79451
NVD CPE · OPERATING SYSTEMmicrosoftwindows_11_22h2Vulnerable target · 1 assertions
Any version (unconstrained) (< 10.0.22621.3155)Canonical identity product-f8c509b6ec25f2a4338a23556be321da5a7c3e8da9f1a4c52f7f15dd0e9a0d2aLinked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:microsoft:windows_11_22h2:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 4
    Logic
    OR
    Version bounds
    through excluding 10.0.22621.3155
    Match ID
    84edbe52-efe0-4d6d-aa76-698b6f9687d1
NVD CPE · OPERATING SYSTEMmicrosoftwindows_11_23h2Vulnerable target · 1 assertions
Any version (unconstrained) (< 10.0.22631.3155)Canonical identity product-026201767813843a6d53867bacde4a55c3035cb868c0a72434012c5e30dab148Linked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 5
    Logic
    OR
    Version bounds
    through excluding 10.0.22631.3155
    Match ID
    900d1da2-6da7-4681-966a-b9973b1329ea
NVD CPE · OPERATING SYSTEMmicrosoftwindows_server_2019Vulnerable target · 1 assertions
Any version (unconstrained) (< 10.0.17763.5458)Canonical identity product-25a2932c0bbcb648f7e391c8b9d34c734e5085444c03c1c206b9d4c4baa80b25Linked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 6
    Logic
    OR
    Version bounds
    through excluding 10.0.17763.5458
    Match ID
    a9098f92-79e7-4762-a37c-99b4cfa8cdd1
NVD CPE · OPERATING SYSTEMmicrosoftwindows_server_2022Vulnerable target · 1 assertions
Any version (unconstrained) (< 10.0.20348.2322)Canonical identity product-d196d31962e613955a91e33e795c22dcfa7bf25173abebaca616a6350cce9ce1Linked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 7
    Logic
    OR
    Version bounds
    through excluding 10.0.20348.2322
    Match ID
    5c8f0436-3afe-48bd-ae92-8f8392dd0a1d
NVD CPE · OPERATING SYSTEMmicrosoftwindows_server_2022_23h2Vulnerable target · 1 assertions
Any version (unconstrained) (<= 10.0.25398.709)Canonical identity product-bc66b50eed682b3633d0f3a2914725d0a72d6d0d5fece14f566d91bc87448c0bLinked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 8
    Logic
    OR
    Version bounds
    through including 10.0.25398.709
    Match ID
    62322dcd-fdd1-4e54-a51a-08d68890e7de

Affected-product evidence

Accepted scope and product mapping

0 canonical links · 2 source-reported links

Source-reported scopeSource-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Vendor specified only by source · Product specified only by source

Source class
Direct cve affected
Assertions
12
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
09b3b047-8141-48b4-9ca9-0c85f56e4c460b1bb616-c4ea-40dc-bd8c-487dc4880ed314ed6478-ec50-4df8-8752-272060374b801c96a5f8-00a9-4f0d-a937-eb57808c20dd59044010-df21-4e47-99f6-ace1b884a99374bd9b16-14b8-474d-b3cc-0c3ba84ea72bc068d1a1-52d1-4072-b43a-689d625d3b5ec7b5bf2f-464e-45a7-9c5f-0715d531c4a0cc030e29-64fd-4e11-9007-9ba3b060b656cdf77de6-461e-4045-b781-5d89d0079519dc3bf0c2-9c6e-45fa-9c40-37231a69dee5eea889c0-81b2-4d09-a670-5021026db774
Source-reported scopeSource-reported scope

Canonical linkage remains open; the cited source assertion is retained below.

Vendor specified only by source · Product specified only by source

Source class
Nvd cpe vulnerable target
Assertions
9
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Aug 27, 2026
Retained assertion IDs
03e2fa3d-acb4-4d90-a4ed-c732eaba4afb0aa27bd5-8f9d-4eef-b36d-12c3df4ed92e0b9e106f-e710-486c-93b4-0e12c8ff84f3152c42d0-3130-448f-b704-6a803539316a2ad2944e-c59d-45a7-9ed3-b21112f661bf8532d8ed-7eb3-49e1-a7b0-ebbd71dd312994a46105-2422-41f0-946f-cba708881126aa60b7c4-92bb-40f5-a9fb-8e071d139fbdba0e01b1-d46e-4798-bd11-898922099b30

Assessments

CVSS by origin

7.8
secure@microsoft.comCVSS 3.1 · role Secondary · priority eligiblevalid_matchCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.8
microsoftCVSS 3.1 · role unknown · display onlyDirect record assessment retained outside normalized eligibilityCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C

Direct CVE/CNA normalized decisions

7.8Priority eligible

microsoft

CVSS 3.1 · Primary · Original assertion · rank 1

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
Validation
Valid match
Recomputed
7.8
Decision reason
Evidence supported
Policy
casca-direct-cvss-eligibility-v1

Assessments are retained side by side under closed precedence. Cascade never averages CVSS.

Evidence boundaries

  • 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; remaining scope stays source-scoped.
  • NVD-carried upstream facts remain derivative; independent corroboration requires a separately authored source.
  • 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.
  • Core replay supports the active and immediately prior generation; retrospective valid-at replay is deferred.
  • OSV aggregation and OSV-converted NVD material are not independent corroboration.
  • Red Hat facts are vendor assertions for the exact supplied products.
  • Nonmembership and not-yet-observed states are not proof of safety.