Evidence dossier

CVE-2026-33824

Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability

Exploited in the wild (CISA KEV since Aug 18, 2026). microsoft reports CVSS 3.1 9.8. EPSS estimates 1.6% exploit likelihood as of Oct 22, 2026.

67.0–80.1Priority evidence range

Evidence through Oct 22, 2026, 6:07 PM UTC

As of Oct 22, 2026

Normalized restatement

Double free in Windows IKE Extension allows an unauthorized attacker to execute code over a network.

State: PUBLISHED
Published: Apr 14, 2026
Updated: Oct 15, 2026
Evidence coverage: 85%

Evidence chronology

What was known when

Download this view's receipt →

Source dateSep 1, 2026First observed by CASCASep 1, 2026
CISA KEV
Exploitation cataloged: Microsoft Internet Key Exchange (IKE) Service Extensions Double Free Vulnerability
Inspect raw assertion
Field
observed_exploitation
Value
Microsoft Internet Key Exchange (IKE) Service Extensions Double Free Vulnerability
Original evidence ↗
Source dateSource date omittedFirst observed by CASCAOct 16, 2026
CISA-ADP
Record text: CISA ADP Vulnrichment
Inspect raw assertion
Field
container
Value
CISA ADP Vulnrichment
Original evidence ↗
Source dateSource date omittedFirst observed by CASCAOct 16, 2026
microsoft
Record text: Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability
Inspect raw assertion
Field
container
Value
Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability
Original evidence ↗
Source dateOct 22, 2026First observed by CASCAOct 22, 2026
FIRST EPSS
EPSS score: 1.62% probability · 75.87th percentile
Inspect raw assertion
Field
model_probability
Value
Probability 0.016190000000; percentile 0.758730000000
Original evidence ↗

ExploitationCatalog member

CISA KEV · catalog date Aug 18, 2026 · first observed Sep 1, 2026

Exploit likelihood1.62%

FIRST EPSS · score date Oct 22, 2026 · 75.9th percentile · first observed Oct 22, 2026

SeverityCVSS 9.8

microsoft · CVSS 3.1 · first observed Oct 16, 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 KEVOriginal assertion

Exploitation cataloged

Microsoft Internet Key Exchange (IKE) Service Extensions Double Free Vulnerability

Inspect raw assertion

Field: observed_exploitation
Value: Microsoft Internet Key Exchange (IKE) Service Extensions Double Free Vulnerability

Source dateSep 1, 2026First observed by CASCASep 1, 2026Original evidence ↗

CISA-ADPIndependent enrichment

Record text

CISA ADP Vulnrichment

Inspect raw assertion

Field: container
Value: CISA ADP Vulnrichment

Source dateSource date omittedFirst observed by CASCAOct 16, 2026Original evidence ↗

microsoftOriginal assertion

Record text

Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability

Inspect raw assertion

Field: container
Value: Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability

Source dateSource date omittedFirst observed by CASCAOct 16, 2026Original evidence ↗

FIRST EPSSOriginal assertion

EPSS score

1.62% probability · 75.87th percentile

Inspect raw assertion

Field: model_probability
Value: Probability 0.016190000000; percentile 0.758730000000

Source dateOct 22, 2026First observed by CASCAOct 22, 2026Original evidence ↗

Applicability

Cited product scope

Trace impact →

23Underlying assertions

13Canonical products

23Target 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

Search scopeRoleOfficial link state

30 scope groups

microsoft · source assertedMicrosoftWindows 10 Version 1607Direct source scope

Affected: 10.0.14393.0 to before 10.0.14393.9060 (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": "10.0.14393.9060", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 10 Version 1809Direct source scope

Affected: 10.0.17763.0 to before 10.0.17763.8644 (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": "10.0.17763.8644", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 10 Version 21H2Direct source scope

Affected: 10.0.19044.0 to before 10.0.19044.7184 (custom comparison)

Source-reported scope

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

Inspect raw assertion

[{"status": "affected", "version": "10.0.19044.0", "lessThan": "10.0.19044.7184", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 10 Version 22H2Direct source scope

Affected: 10.0.19045.0 to before 10.0.19045.7184 (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": "10.0.19045.7184", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 11 version 23H2Direct source scope

Affected: 10.0.22631.0 to before 10.0.22631.6936 (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": "10.0.22631.6936", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 11 Version 23H2Direct source scope

Affected: 10.0.22631.0 to before 10.0.22631.6936 (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": "10.0.22631.6936", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 11 Version 24H2Direct source scope

Affected: 10.0.26100.0 to before 10.0.26100.8246 (custom comparison)

Source-reported scope

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

Inspect raw assertion

[{"status": "affected", "version": "10.0.26100.0", "lessThan": "10.0.26100.8246", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 11 Version 25H2Direct source scope

Affected: 10.0.26200.0 to before 10.0.26200.8246 (custom comparison)

Source-reported scope

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

Inspect raw assertion

[{"status": "affected", "version": "10.0.26200.0", "lessThan": "10.0.26200.8246", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 11 version 26H1Direct source scope

Affected: 10.0.28000.0 to before 10.0.28000.1836 (custom comparison)

Source-reported scope

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

Inspect raw assertion

[{"status": "affected", "version": "10.0.28000.0", "lessThan": "10.0.28000.1836", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2016Direct source scope

Affected: 10.0.14393.0 to before 10.0.14393.9060 (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": "10.0.14393.9060", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2016 (Server Core installation)Direct source scope

Affected: 10.0.14393.0 to before 10.0.14393.9060 (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": "10.0.14393.9060", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2019Direct source scope

Affected: 10.0.17763.0 to before 10.0.17763.8644 (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": "10.0.17763.8644", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2019 (Server Core installation)Direct source scope

Affected: 10.0.17763.0 to before 10.0.17763.8644 (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": "10.0.17763.8644", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2022Direct source scope

Affected: 10.0.20348.0 to before 10.0.20348.5020 (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": "10.0.20348.5020", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2022, 23H2 Edition (Server Core installation)Direct source scope

Affected: 10.0.25398.0 to before 10.0.25398.2274 (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": "10.0.25398.2274", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2025Direct source scope

Affected: 10.0.26100.0 to before 10.0.26100.32690 (custom comparison)

Source-reported scope

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

Inspect raw assertion

[{"status": "affected", "version": "10.0.26100.0", "lessThan": "10.0.26100.32690", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2025 (Server Core installation)Direct source scope

Affected: 10.0.26100.0 to before 10.0.26100.32690 (custom comparison)

Source-reported scope

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

Inspect raw assertion

[{"status": "affected", "version": "10.0.26100.0", "lessThan": "10.0.26100.32690", "versionType": "custom"}]

NVD CPE · OPERATING SYSTEMmicrosoftwindows_10_1607Vulnerable target · 2 assertions

Any version (unconstrained) (< 10.0.14393.9060)Canonical identity product-740fec3e9838b5eabe76ebe27e4d0d7a4cb2e0ef7e13923300d3d0b51e3fce1cLinked exact

Scope supported

Inspect raw assertions

cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x64:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 0
Logic
OR
Version bounds
through excluding 10.0.14393.9060
Match ID
158c16a3-547e-4130-8428-8e429c37e573
cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x86:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 1
Logic
OR
Version bounds
through excluding 10.0.14393.9060
Match ID
58e1a340-d49a-4ebb-a750-876922acd5ca

NVD CPE · OPERATING SYSTEMmicrosoftwindows_10_1809Vulnerable target · 2 assertions

Any version (unconstrained) (< 10.0.17763.8644)Canonical identity product-a3084138383423221f61594e86f5b295e5e254acd7ae5284f45e0877a084db43Linked exact

Scope supported

Inspect raw assertions

cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 3
Logic
OR
Version bounds
through excluding 10.0.17763.8644
Match ID
9b1465b1-bde6-4634-8f12-43f71d68a4d6
cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 2
Logic
OR
Version bounds
through excluding 10.0.17763.8644
Match ID
64248504-2307-45fc-8ff3-7a227cfd8675

NVD CPE · OPERATING SYSTEMmicrosoftwindows_10_21h2Vulnerable target · 3 assertions

Any version (unconstrained) (< 10.0.19044.7184)Canonical identity product-ec10c9f400f23fdf118887f60fe116ffde4adb76dcf118cdd3a7556fd033da3bLinked exact

Scope supported

Inspect raw assertions

cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:arm64:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 4
Logic
OR
Version bounds
through excluding 10.0.19044.7184
Match ID
88a175c4-e033-4fe7-b2bf-8bae14321bc4
cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x86:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 6
Logic
OR
Version bounds
through excluding 10.0.19044.7184
Match ID
c375372b-d3d4-4b11-aad8-69ac344c24bc
cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x64:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 5
Logic
OR
Version bounds
through excluding 10.0.19044.7184
Match ID
86dbf14a-f486-4fe7-9126-d1d54952fc6c

NVD CPE · OPERATING SYSTEMmicrosoftwindows_10_22h2Vulnerable target · 3 assertions

Any version (unconstrained) (< 10.0.19045.7184)Canonical identity product-a6295b9daad3ca57ce70751badba5b7fe99229c8a562cc7400e8cfef3daccaeeLinked exact

Scope supported

Inspect raw assertions

cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x64:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 8
Logic
OR
Version bounds
through excluding 10.0.19045.7184
Match ID
269b8e88-6473-41dd-ba33-d9184b82ca58
cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:arm64:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 7
Logic
OR
Version bounds
through excluding 10.0.19045.7184
Match ID
8ce2e268-e776-4697-9e43-33aba4cdbe05
cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x86:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 9
Logic
OR
Version bounds
through excluding 10.0.19045.7184
Match ID
fcbb431b-ef21-4454-bda3-d8f276be7a64

NVD CPE · OPERATING SYSTEMmicrosoftwindows_11_23h2Vulnerable target · 2 assertions

Any version (unconstrained) (< 10.0.22631.6936)Canonical identity product-026201767813843a6d53867bacde4a55c3035cb868c0a72434012c5e30dab148Linked exact

Scope supported

Inspect raw assertions

cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:arm64:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 10
Logic
OR
Version bounds
through excluding 10.0.22631.6936
Match ID
b33ce091-b873-4c30-ba05-54a8c1839212
cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:x64:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 11
Logic
OR
Version bounds
through excluding 10.0.22631.6936
Match ID
e3af28f3-d486-4b88-9e0e-371241024174

NVD CPE · OPERATING SYSTEMmicrosoftwindows_11_24h2Vulnerable target · 2 assertions

Any version (unconstrained) (< 10.0.26100.8246)Canonical identity product-8665879a2f5fe8b8eab868c43d6ace340b95d1f3879639d97ebdf60ef7b49b5fLinked exact

Scope supported

Inspect raw assertions

cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:arm64:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 12
Logic
OR
Version bounds
through excluding 10.0.26100.8246
Match ID
94eb36c7-1ff2-4b44-ad91-f3540f09393e
cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:x64:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 13
Logic
OR
Version bounds
through excluding 10.0.26100.8246
Match ID
14b23c3f-c8ac-491a-bca5-eb6982c8f9e9

NVD CPE · OPERATING SYSTEMmicrosoftwindows_11_25h2Vulnerable target · 2 assertions

Any version (unconstrained) (< 10.0.26200.8246)Canonical identity product-e9349aae7bae97a590ecc61309b626fd2c236f349da7ff6c765ab3d5cefdfa78Linked exact

Scope supported

Inspect raw assertions

cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:x64:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 15
Logic
OR
Version bounds
through excluding 10.0.26200.8246
Match ID
adc6ce99-ab5d-4dd5-82a9-892366c4b2fd
cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:arm64:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 14
Logic
OR
Version bounds
through excluding 10.0.26200.8246
Match ID
361b5dab-8d1f-45d7-a33c-f49eba56b5f8

NVD CPE · OPERATING SYSTEMmicrosoftwindows_11_26h1Vulnerable target · 2 assertions

Any version (unconstrained) (< 10.0.28000.1836)Canonical identity product-2bea232ffaff2e2d98c0ee9cff13584b133589ad790ac6de44c17e3947efc900Linked exact

Scope supported

Inspect raw assertions

cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 17
Logic
OR
Version bounds
through excluding 10.0.28000.1836
Match ID
13a01fa1-08dc-4e33-9ffc-ab4bcd9634ca
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:*
Official link
Linked exact
Role
Vulnerable target
Configuration
0 · node/0 · match 16
Logic
OR
Version bounds
through excluding 10.0.28000.1836
Match ID
690e74a8-e72c-47b6-96eb-37c48d69a635

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: 17
Mapping revision: cpe23-exact-mapping-v1
Observed cutoff: Oct 22, 2026

Retained assertion IDs

0d1a2e85-8080-43a6-8f22-cb12ba103ca012e004ca-60c3-486d-b3a3-d21fbe8e721915629299-4741-4e64-9363-57dc512ea1a1232285dd-595c-4fd0-83c6-74a7624b956641e7fbb2-3acd-45eb-8c17-2c01e6894b5044158dde-0fee-4e18-95e7-32287ed3430b45886c32-4214-43fd-9cb7-47556cef61e84aeda4dc-6af9-4acf-8050-f73c2741793650b13ee3-dfef-4abf-bac5-156fc6434cd251e6d288-53d8-4eda-a636-9ccb623de0948af937ed-875a-4edf-a9d0-1ef4299e65c5997d89c2-5615-4de3-8a4b-268837d8b49dcb3d0fac-0508-4940-8624-075b18e80e6cdd37d46c-77c9-4a75-9ea4-cf4bb3da0b95e06d914c-e71b-4ab3-88fd-dcad1dcc6c90e82e37cb-b4ae-4f0e-a052-38b78be4a71ffdc43b6c-3d23-4537-bac3-bf3314955296

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: 23
Mapping revision: cpe23-exact-mapping-v1
Observed cutoff: Oct 22, 2026

Retained assertion IDs

133e9bc2-783e-4201-89c4-2d38a41a86921c3defbf-9052-4c3a-961b-54acd3f02c4735b21319-64c0-4be2-bd2f-a01f6de7c3a7428248ec-6402-4a9f-87c9-2881fe989f6347e100e7-3680-408a-9742-35ace1ff2d9e4cae8a58-0f8f-4609-99fa-614cd4e357484f783545-229c-428e-aad7-1f960866da846006df65-ebaa-44fe-8eff-e3ebed654c5a6518f9f0-5bf6-4894-8711-97921913187973a3eb7a-e036-406f-9db0-9fc06a4823539684cbb4-bd26-4cdd-92cf-f7c9b47c42baa284a67a-13de-4e78-8a52-5e88fa6d8130a9e00e29-d3db-41d5-ad6e-87fd96551125b09fda6a-ec70-4fb3-9698-afac3ab59c33bc208c4b-d928-4444-b5cd-1a5a0e613783bee5cb15-d851-46a8-a0f8-574d857b370ac0ba2c7c-a06c-48cb-a8b2-ea4aca497327d402a022-0e7b-4465-9157-fc74dccf449cd8de4ad5-d9c7-4b8a-96ae-09d4a85974f1f1fc7115-9719-4ed4-8b75-32e485c74423f6899cdb-fc4b-4a91-989d-04b70b39c605f7cd165e-ef87-484a-854d-3ea09d992b20f7e312c0-4779-45be-b56e-eac2411c130b

Assessments

CVSS by origin

9.8

secure@microsoft.comCVSS 3.1 · role Secondary · priority eligiblevalid_matchCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

9.8

microsoftCVSS 3.1 · role unknown · display onlyDirect record assessment retained outside normalized eligibilityCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Direct CVE/CNA normalized decisions

9.8Priority eligible

microsoft

CVSS 3.1 · Primary · Original assertion · rank 1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Validation: Valid match
Recomputed: 9.8
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.