Evidence dossier

CVE-2023-23376

Windows Common Log File System Driver Elevation of Privilege Vulnerability

Exploited in the wild (CISA KEV since Feb 14, 2023). microsoft reports CVSS 3.1 7.8. EPSS estimates 10.9% exploit likelihood as of Aug 27, 2026.

66.1–79.0Priority evidence range

Evidence current through Aug 27, 2026, 6:09 PM UTC

As of Aug 27, 2026

Normalized restatement

Windows Common Log File System Driver Elevation of Privilege Vulnerability

State: PUBLISHED
Published: Feb 14, 2023
Updated: Aug 5, 2026
Evidence coverage: 85%

Evidence chronology

What was known when

Download this view's receipt →

Source dateJul 16, 2026First observed by CASCAJul 19, 2026
CISA KEV
Exploitation cataloged: Microsoft Windows Common Log File System (CLFS) Driver Privilege Escalation Vulnerability
Inspect raw assertion
Field
observed_exploitation
Value
Microsoft Windows Common Log File System (CLFS) Driver Privilege Escalation Vulnerability
Original evidence ↗
Source dateSource date omittedFirst observed by CASCAAug 6, 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 CASCAAug 6, 2026
CVE Program
Record text: CVE Program Container
Inspect raw assertion
Field
container
Value
CVE Program Container
Original evidence ↗
Source dateSource date omittedFirst observed by CASCAAug 6, 2026
microsoft
Record text: Windows Common Log File System Driver Elevation of Privilege Vulnerability
Inspect raw assertion
Field
container
Value
Windows Common Log File System Driver Elevation of Privilege Vulnerability
Original evidence ↗
Source dateAug 27, 2026First observed by CASCAAug 27, 2026
FIRST EPSS
EPSS score: 10.85% probability · 95.52th percentile
Inspect raw assertion
Field
model_probability
Value
Probability 0.108530000000; percentile 0.955240000000
Original evidence ↗

ExploitationCatalog member

CISA KEV · catalog date Feb 14, 2023 · first observed Jul 19, 2026

Exploit likelihood10.85%

FIRST EPSS · score date Aug 27, 2026 · 95.5th percentile · first observed Aug 27, 2026

SeverityCVSS 7.8

microsoft · CVSS 3.1 · first observed Aug 6, 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 Common Log File System (CLFS) Driver Privilege Escalation Vulnerability

Inspect raw assertion

Field: observed_exploitation
Value: Microsoft Windows Common Log File System (CLFS) Driver Privilege Escalation Vulnerability

Source dateJul 16, 2026First observed by CASCAJul 19, 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 CASCAAug 6, 2026Original evidence ↗

CVE ProgramDerivative copy

Record text

CVE Program Container

Inspect raw assertion

Field: container
Value: CVE Program Container

Source dateSource date omittedFirst observed by CASCAAug 6, 2026Original evidence ↗

microsoftOriginal assertion

Record text

Windows Common Log File System Driver Elevation of Privilege Vulnerability

Inspect raw assertion

Field: container
Value: Windows Common Log File System Driver Elevation of Privilege Vulnerability

Source dateSource date omittedFirst observed by CASCAAug 6, 2026Original evidence ↗

FIRST EPSSOriginal assertion

EPSS score

10.85% probability · 95.52th percentile

Inspect raw assertion

Field: model_probability
Value: Probability 0.108530000000; percentile 0.955240000000

Source dateAug 27, 2026First observed by CASCAAug 27, 2026Original evidence ↗

Applicability

Cited product scope

Trace impact →

15Underlying assertions

13Canonical products

15Target 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

36 scope groups

microsoft · source assertedMicrosoftWindows 10 Version 1507Direct source scope

Affected: 10.0.10240.0 to before 10.0.10240.19747 (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": "10.0.10240.19747", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 10 Version 1607Direct source scope

Affected: 10.0.14393.0 to before 10.0.14393.5717 (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": "10.0.14393.5717", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 10 Version 1809Direct source scope

Affected: 10.0.17763.0 to before 10.0.17763.4010 (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": "10.0.17763.4010", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 10 Version 1809Direct source scope

Affected: 10.0.0 to before 10.0.17763.4010 (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": "10.0.17763.4010", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 10 Version 20H2Direct source scope

Affected: 10.0.0 to before 10.0.19042.2604 (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": "10.0.19042.2604", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 10 Version 21H2Direct source scope

Affected: 10.0.19043.0 to before 10.0.19044.2604 (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": "10.0.19044.2604", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 10 Version 22H2Direct source scope

Affected: 10.0.19045.0 to before 10.0.19045.2604 (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": "10.0.19045.2604", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 11 version 21H2Direct source scope

Affected: 10.0.0 to before 10.0.22621.1574 (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": "10.0.22621.1574", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows 11 version 22H2Direct source scope

Affected: 10.0.22621.0 to before 10.0.22621.1265 (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": "10.0.22621.1265", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2008 R2 Service Pack 1Direct source scope

Affected: 6.1.7601.0 to before 6.1.7601.26366 (custom comparison)

Source-reported scope

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

Inspect raw assertion

[{"status": "affected", "version": "6.1.7601.0", "lessThan": "6.1.7601.26366", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2008 R2 Service Pack 1 (Server Core installation)Direct source scope

Affected: 6.1.7601.0 to before 6.1.7601.26366 (custom comparison)

Source-reported scope

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

Inspect raw assertion

[{"status": "affected", "version": "6.1.7601.0", "lessThan": "6.1.7601.26366", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2008 Service Pack 2Direct source scope

Affected: 6.0.6003.0 to before 6.0.6003.21915 (custom comparison)

Source-reported scope

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

Inspect raw assertion

[{"status": "affected", "version": "6.0.6003.0", "lessThan": "6.0.6003.21915", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2008 Service Pack 2Direct source scope

Affected: 6.0.6003.0 to before 6.0.6003.21915 (custom comparison)

Source-reported scope

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

Inspect raw assertion

[{"status": "affected", "version": "6.0.6003.0", "lessThan": "6.0.6003.21915", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2008 Service Pack 2 (Server Core installation)Direct source scope

Affected: 6.0.6003.0 to before 6.0.6003.21915 (custom comparison)

Source-reported scope

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

Inspect raw assertion

[{"status": "affected", "version": "6.0.6003.0", "lessThan": "6.0.6003.21915", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2012Direct source scope

Affected: 6.2.9200.0 to before 6.2.9200.24116 (custom comparison)

Source-reported scope

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

Inspect raw assertion

[{"status": "affected", "version": "6.2.9200.0", "lessThan": "6.2.9200.24116", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2012 R2Direct source scope

Affected: 6.3.9600.0 to before 6.3.9600.20821 (custom comparison)

Source-reported scope

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

Inspect raw assertion

[{"status": "affected", "version": "6.3.9600.0", "lessThan": "6.3.9600.20821", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2012 R2 (Server Core installation)Direct source scope

Affected: 6.3.9600.0 to before 6.3.9600.20821 (custom comparison)

Source-reported scope

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

Inspect raw assertion

[{"status": "affected", "version": "6.3.9600.0", "lessThan": "6.3.9600.20821", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2012 (Server Core installation)Direct source scope

Affected: 6.2.9200.0 to before 6.2.9200.24116 (custom comparison)

Source-reported scope

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

Inspect raw assertion

[{"status": "affected", "version": "6.2.9200.0", "lessThan": "6.2.9200.24116", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2016Direct source scope

Affected: 10.0.14393.0 to before 10.0.14393.5717 (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": "10.0.14393.5717", "versionType": "custom"}]

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

Affected: 10.0.14393.0 to before 10.0.14393.5717 (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": "10.0.14393.5717", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2019Direct source scope

Affected: 10.0.17763.0 to before 10.0.17763.4010 (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": "10.0.17763.4010", "versionType": "custom"}]

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

Affected: 10.0.17763.0 to before 10.0.17763.4010 (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": "10.0.17763.4010", "versionType": "custom"}]

microsoft · source assertedMicrosoftWindows Server 2022Direct source scope

Affected: 10.0.20348.0 to before 10.0.20348.1547 (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": "10.0.20348.1547", "versionType": "custom"}]

NVD CPE · OPERATING SYSTEMmicrosoftwindows_10_1507Vulnerable target · 1 assertions

Any version (unconstrained) (< 10.0.10240.19747)Canonical identity product-9851bd571b8ab08bca589cd73710badfef557d036f0fb7707f694f1c9f597cb4Linked exact

Scope supported

Inspect raw assertion

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 10.0.10240.19747
Match ID
a4172403-c3de-4f91-8e9d-37785290064b

NVD CPE · OPERATING SYSTEMmicrosoftwindows_10_1607Vulnerable target · 1 assertions

Any version (unconstrained) (< 10.0.14393.5717)Canonical identity product-740fec3e9838b5eabe76ebe27e4d0d7a4cb2e0ef7e13923300d3d0b51e3fce1cLinked exact

Scope supported

Inspect raw assertion

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 10.0.14393.5717
Match ID
092a553e-da52-4e5a-a166-9c864be93d12

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: 23
Mapping revision: cpe23-exact-mapping-v1
Observed cutoff: Aug 27, 2026

Retained assertion IDs

03eb7520-aea7-4dfc-843c-8d26870d8b821b00c6c4-3988-4bab-9097-57dfe2856eed2b04b065-9d19-4e56-adb1-0445f7d755ae3f14950c-e3f8-48d7-95b6-e4df02c52b114727f3de-3989-4fe8-957c-efbbcb80ba3b47470752-f658-4125-bc5b-0723466c1fec59046819-50ec-495a-ac8b-c60bb70a9d11596c3adf-e0b7-48a8-bc80-cfc97a37d5605e2b6c03-6cab-4328-b476-a3c07342521d7331a1e7-87f2-44f0-ab19-97bac2ce7ba67376941c-46dd-419b-9bb6-6ea63423305077c869b1-3a49-44f3-ba4e-7ca3a347097679c6b0fb-5a1e-43ea-8ecc-890d59e002f27e970c36-c537-431c-81bf-634433364a80805fe7ae-32a0-481b-be03-d1dd06881c408fc140ee-b9f9-49c4-943e-24cd73b4e51ab0aff545-2a45-438c-b8e1-68878329709fc7c632f1-1b24-445c-8d08-5ce625e403b8e37649d5-004d-4c6d-9837-82c544e3209ee9a13a49-557b-4493-95b0-8b602f5834bcf2a3b2dc-6ee3-4b3b-9da4-9737d88476c4fb0ccd4a-a56b-4f24-9e93-507a6567c6c0fd2133d0-59af-4fa0-9f8d-180fecac4037

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: 15
Mapping revision: cpe23-exact-mapping-v1
Observed cutoff: Aug 27, 2026

Retained assertion IDs

062049b1-4ca0-4157-966c-54873571b3020e9c75cd-ae8a-4112-b762-a5c9467d0bc116cd0db2-f6d9-41a2-a40e-f4c6e361caca16f2e17a-611c-4191-bd5c-3ffc5ed3583951c5e30d-073a-43c7-8773-b14a1234aaad53dda4a6-bb94-48bb-9799-7f241c616ced568f3994-416e-47ef-9129-9b974ac802a17da09654-53e7-4d5e-8339-66531f9ad1bf963c6517-7bb8-466e-9e0d-800b2391a50bb33cb317-f093-4355-9d51-9a62c7fa7e39b41df018-4f92-453a-84d3-1b38b7adaa79b81d406a-bc19-4aec-b112-321c4df5ad38d3f21f21-87dd-4a2d-9bfa-a4f9afd007d7e6445c31-de83-4ce5-9c25-d89d0219567ce7634644-a2d3-4605-97d3-9acc73c93249

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:U/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:U/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.