CASCACascade Atlas

Evidence dossier

CVE-2024-21351

Windows SmartScreen Security Feature Bypass Vulnerability

Exploited in the wild (CISA KEV since Feb 13, 2024). microsoft reports CVSS 3.1 7.6. EPSS estimates 27.8% exploit likelihood as of Oct 22, 2026.

69.5–81.6Priority evidence range
Evidence through Oct 22, 2026, 6:07 PM UTC

As of Oct 22, 2026

Normalized restatement

Windows SmartScreen Security Feature Bypass Vulnerability

State
PUBLISHED
Published
Feb 13, 2024
Updated
Aug 10, 2026
Evidence coverage
85%

Evidence chronology

What was known when

Download this view's receipt →
  1. 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 ↗
  2. 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 ↗
  3. Source dateSource date omittedFirst observed by CASCA
    microsoft

    Record text: Windows SmartScreen Security Feature Bypass Vulnerability

    Inspect raw assertion
    Field
    container
    Value
    Windows SmartScreen Security Feature Bypass Vulnerability
    Original evidence ↗
  4. Source dateFirst observed by CASCA
    CISA KEV

    Exploitation cataloged: Microsoft Windows SmartScreen Security Feature Bypass Vulnerability

    Inspect raw assertion
    Field
    observed_exploitation
    Value
    Microsoft Windows SmartScreen Security Feature Bypass Vulnerability
    Original evidence ↗
  5. Source dateFirst observed by CASCA
    FIRST EPSS

    EPSS score: 27.8% probability · 98.09th percentile

    Inspect raw assertion
    Field
    model_probability
    Value
    Probability 0.277980000000; percentile 0.980930000000
    Original evidence ↗
ExploitationCatalog member

CISA KEV · catalog date Feb 13, 2024 · first observed Sep 1, 2026

Exploit likelihood27.80%

FIRST EPSS · score date Oct 22, 2026 · 98.1th percentile · first observed Oct 22, 2026

SeverityCVSS 7.6

microsoft · CVSS 3.1 · first observed Aug 10, 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 statusLast verified source snapshot retained

The last verified source boundary remains in force for this claim.

Revision
evidence-policy-v1.1.0
Cutoff
Oct 22, 2026
Resolution
Review source contract
Exploit likelihoodEvidence supported

Eligible evidence is present for this bounded claim.

Revision
evidence-policy-v1.1.0
Cutoff
Oct 22, 2026
Resolution
None
Severity assessmentEvidence supported

Eligible evidence is present for this bounded claim.

Revision
casca-direct-cvss-eligibility-v1
Cutoff
Oct 22, 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
Oct 22, 2026
Resolution
Resolve identity

Source comparison

Who said what

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 SmartScreen Security Feature Bypass Vulnerability

Inspect raw assertion
Field
container
Value
Windows SmartScreen Security Feature Bypass Vulnerability
Source dateSource date omittedFirst observed by CASCAOriginal evidence ↗
CISA KEVOriginal assertion
Exploitation cataloged

Microsoft Windows SmartScreen Security Feature Bypass Vulnerability

Inspect raw assertion
Field
observed_exploitation
Value
Microsoft Windows SmartScreen Security Feature Bypass Vulnerability
Source dateFirst observed by CASCAOriginal evidence ↗
FIRST EPSSOriginal assertion
EPSS score

27.8% probability · 98.09th percentile

Inspect raw assertion
Field
model_probability
Value
Probability 0.277980000000; percentile 0.980930000000
Source dateFirst observed by CASCAOriginal evidence ↗

Applicability

Cited product scope

Trace impact →
12Underlying assertions
12Canonical products
12Target 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

25 scope groups

microsoft · source assertedMicrosoftWindows 10 Version 1507Direct source scope
Affected: 10.0.10240.0 to before 10.0.10240.20469 (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "10.0.10240.0", "lessThan": "10.0.10240.20469", "versionType": "custom"}]
microsoft · source assertedMicrosoftWindows 10 Version 1607Direct source scope
Affected: 10.0.14393.0 to before 10.0.14393.6709 (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "10.0.14393.0", "lessThan": "10.0.14393.6709", "versionType": "custom"}]
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 2016Direct source scope
Affected: 10.0.14393.0 to before 10.0.14393.6709 (custom comparison)
Source-reported scope

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

Inspect raw assertion[{"status": "affected", "version": "10.0.14393.0", "lessThan": "10.0.14393.6709", "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 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"}]
NVD CPE · OPERATING SYSTEMmicrosoftwindows_10_1507Vulnerable target · 1 assertions
Any version (unconstrained) (< 10.0.10240.20469)Canonical identity product-9851bd571b8ab08bca589cd73710badfef557d036f0fb7707f694f1c9f597cb4Linked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:microsoft:windows_10_1507:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 0
    Logic
    OR
    Version bounds
    through excluding 10.0.10240.20469
    Match ID
    448534ce-1c07-4df1-8edd-c43c3492898b
NVD CPE · OPERATING SYSTEMmicrosoftwindows_10_1607Vulnerable target · 1 assertions
Any version (unconstrained) (< 10.0.14393.6709)Canonical identity product-740fec3e9838b5eabe76ebe27e4d0d7a4cb2e0ef7e13923300d3d0b51e3fce1cLinked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 1
    Logic
    OR
    Version bounds
    through excluding 10.0.14393.6709
    Match ID
    2d282e53-abbf-4832-9c93-a988586ae96e
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 2
    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 3
    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 4
    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 5
    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 6
    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 7
    Logic
    OR
    Version bounds
    through excluding 10.0.22631.3155
    Match ID
    900d1da2-6da7-4681-966a-b9973b1329ea
NVD CPE · OPERATING SYSTEMmicrosoftwindows_server_2016Vulnerable target · 1 assertions
Version not applicableCanonical identity product-02e254d111ce604757a15650ef469f4f8365d6247da82ce3ac2695c3cfc7dc5fLinked exact
Scope supported
Inspect raw assertion
  1. cpe:2.3:o:microsoft:windows_server_2016:-:*:*:*:*:*:*:*
    Official link
    Linked exact
    Role
    Vulnerable target
    Configuration
    0 · node/0 · match 8
    Logic
    OR
    Version bounds
    No explicit bounds
    Match ID
    041ff8ba-0b12-4a1f-b4bf-9c4f33b7c1e7
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 9
    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 10
    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 11
    Logic
    OR
    Version bounds
    through excluding 10.0.25398.709
    Match ID
    b6fcf1a0-6b8e-457a-ab6a-2de939b9d18b

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
13
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Oct 22, 2026
Retained assertion IDs
036fdf9f-0ee8-4173-80d1-4946d6c860c1087f8d60-e4e2-4d12-aee0-7dc869a47a830b0f4051-8487-47a6-b19d-23a9977bba800efe3c4d-4751-4533-bc97-441cf81f9a902c025d2a-993b-4343-a34b-a9c7b94a992e2d4dbe6e-99cf-46cc-9096-66c9403f282c31c04452-5e40-421d-a987-7a4ff44b02a138d405cf-854a-41d8-bea6-2707e20b177fb28e67f3-b73a-46ca-88b6-1dfed9c07d03bd51be03-67a3-42d0-b654-4036d0022175c4282a0f-0de8-4b1f-b257-3630bf667aeccc28b276-a8d8-40e2-94e3-958eaf842f0cccc56da2-cf32-438f-93d6-8bbdd30ea084
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
12
Mapping revision
cpe23-exact-mapping-v1
Observed cutoff
Oct 22, 2026
Retained assertion IDs
0a31881f-21e7-47af-b9cb-770945dd8c44123810e7-4360-4068-98f6-976d46ee706a172ccbc5-1f72-4cf4-85d1-1c00976775223563f13d-4cfa-467b-8243-d316d0f271fe5412e409-bbf5-4549-b34e-877ae2414e6b8857ead1-21dd-4fc5-b7bf-fe1756ff54108b312736-e4ef-4203-b105-936b82044849abd8c8ed-2f2d-475c-a7a6-4c02358c789bc633cc62-6fa2-42d8-8a38-80fc7e4cd62cc7e47206-c868-48dd-a74f-064d77c5aa68ec75c3c6-cb4d-48b0-85a5-dd5137f89b21f936f3fe-d62b-4698-bf22-63668a9aff13

Assessments

CVSS by origin

7.6
secure@microsoft.comCVSS 3.1 · role Secondary · priority eligiblevalid_matchCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:L
7.6
microsoftCVSS 3.1 · role unknown · display onlyDirect record assessment retained outside normalized eligibilityCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:L/E:U/RL:O/RC:C

Direct CVE/CNA normalized decisions

7.6Priority eligible

microsoft

CVSS 3.1 · Primary · Original assertion · rank 1

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:L/E:U/RL:O/RC:C
Validation
Valid match
Recomputed
7.6
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.