CISA KEV · catalog date Feb 15, 2024 · first observed Jul 19, 2026
Evidence dossier
CVE-2024-21410
Microsoft Exchange Server Elevation of Privilege Vulnerability
Exploited in the wild (CISA KEV since Feb 15, 2024). microsoft reports CVSS 3.1 9.8. EPSS estimates 12.7% exploit likelihood as of Aug 27, 2026.
As of Aug 27, 2026
Normalized restatement
Microsoft Exchange Server Elevation of Privilege Vulnerability
- State
- PUBLISHED
- Published
- Feb 13, 2024
- Updated
- Oct 21, 2025
- Evidence coverage
- 92%
Evidence chronology
What was known when
- Source dateSource date omittedFirst observed by CASCACISA-ADPOriginal evidence ↗
Record text: CISA ADP Vulnrichment
Inspect raw assertion
- Field
container- Value
- CISA ADP Vulnrichment
- Source dateSource date omittedFirst observed by CASCACVE ProgramOriginal evidence ↗
Record text: CVE Program Container
Inspect raw assertion
- Field
container- Value
- CVE Program Container
- Source dateSource date omittedFirst observed by CASCAmicrosoftOriginal evidence ↗
Record text: Microsoft Exchange Server Elevation of Privilege Vulnerability
Inspect raw assertion
- Field
container- Value
- Microsoft Exchange Server Elevation of Privilege Vulnerability
- Source dateFirst observed by CASCACISA KEVOriginal evidence ↗
Exploitation cataloged: Microsoft Exchange Server Privilege Escalation Vulnerability
Inspect raw assertion
- Field
observed_exploitation- Value
- Microsoft Exchange Server Privilege Escalation Vulnerability
- Source dateFirst observed by CASCAFIRST EPSSOriginal evidence ↗
EPSS score: 12.66% probability · 95.96th percentile
Inspect raw assertion
- Field
model_probability- Value
- Probability 0.126610000000; percentile 0.959550000000
FIRST EPSS · score date Aug 27, 2026 · 96th percentile · first observed Aug 27, 2026
microsoft · CVSS 3.1 · first observed Jul 19, 2026 · same-version scores align in this snapshot
Evidence detail
Source limits and decisions
Why each evidence state has this value
casca-unknown-reasons-v1Eligible evidence is present for this bounded claim.
- Revision
- evidence-policy-v1.1.0
- Cutoff
- Aug 27, 2026
- Resolution
- None
Eligible evidence is present for this bounded claim.
- Revision
- evidence-policy-v1.1.0
- Cutoff
- Aug 27, 2026
- Resolution
- None
Eligible evidence is present for this bounded claim.
- Revision
- casca-direct-cvss-eligibility-v1
- Cutoff
- Aug 27, 2026
- Resolution
- None
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 ADP Vulnrichment
Inspect raw assertion
- Field
container- Value
- CISA ADP Vulnrichment
CVE Program Container
Inspect raw assertion
- Field
container- Value
- CVE Program Container
Microsoft Exchange Server Elevation of Privilege Vulnerability
Inspect raw assertion
- Field
container- Value
- Microsoft Exchange Server Elevation of Privilege Vulnerability
Microsoft Exchange Server Privilege Escalation Vulnerability
Inspect raw assertion
- Field
observed_exploitation- Value
- Microsoft Exchange Server Privilege Escalation Vulnerability
12.66% probability · 95.96th percentile
Inspect raw assertion
- Field
model_probability- Value
- Probability 0.126610000000; percentile 0.959550000000
Applicability
Cited product scope
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 2026-07-21T06:45:29.809Z
27d65b0f-b718-4b4f-bb79-c47c68d09dfa - Cpe match643,502 records · observed through 2026-07-21T08:13:17.697Z
955dae73-7302-438b-aee1-058d7cc5d48e
4 scope groups
Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "15.01.0", "lessThan": "15.01.2507.037", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "15.02.0", "lessThan": "15.2.1544.004", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "15.02.0", "lessThan": "15.2.1544.004", "versionType": "custom"}]product-d87daca995d075bf30565cc429e7242a47683272975068df1d327ec1d8ff609cLinked exactInspect raw assertions
cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_13:*:*:*:*:*:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 1
- Logic
- OR
- Version bounds
- No explicit bounds
- Match ID
583745c7-b802-4cbe-bd88-b5b9af9b5371
cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_23:*:*:*:*:*:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 0
- Logic
- OR
- Version bounds
- No explicit bounds
- Match ID
ff76aeda-e574-40ed-b64f-8fdef8cac802
cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_14:*:*:*:*:*:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 2
- Logic
- OR
- Version bounds
- No explicit bounds
- Match ID
8c98993b-82a5-48cc-947f-896cea0cdb7f
Affected-product evidence
Accepted scope and product mapping
1 canonical links · 1 source-reported links
vendor-01299a5a765aea70faa05f2d06e0c26a5d498fd34553e868d89e8a43b31864db · product-d87daca995d075bf30565cc429e7242a47683272975068df1d327ec1d8ff609c
- Source class
- Nvd cpe vulnerable target
- Assertions
- 3
- Mapping revision
- cpe23-exact-mapping-v1
- Observed cutoff
- Aug 27, 2026
Retained assertion IDs
3edb6ccb-96f5-4ebc-b684-525eda55eaf3b31971b9-9da2-4601-be23-119980b3f270c62c9e5b-899e-4624-9dc6-7a6e087a7f3dCanonical 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
- 3
- Mapping revision
- cpe23-exact-mapping-v1
- Observed cutoff
- Aug 27, 2026
Retained assertion IDs
0b623751-52b9-4282-b6a4-7ac20728dbcd97e0b61b-b473-4fd2-ba62-905e74206975d1679dd4-b85a-4c38-9792-4bd9f8f3109dAssessments
CVSS by origin
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:CDirect CVE/CNA normalized decisions
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:F/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.