CISA KEV · catalog date Mar 3, 2022 · first observed Jul 19, 2026
Evidence dossier
CVE-2018-8581
An elevation of privilege vulnerability exists in Microsoft Exchange Server, aka "Microsoft Exchange Server Elevation of Privilege Vulnerability." This affects Microsoft…
Exploited in the wild (CISA KEV since Mar 3, 2022). NVD reports CVSS 3.1 7.4. EPSS estimates 27.4% exploit likelihood as of Aug 27, 2026.
As of Aug 27, 2026
Normalized restatement
An elevation of privilege vulnerability exists in Microsoft Exchange Server, aka "Microsoft Exchange Server Elevation of Privilege Vulnerability." This affects Microsoft Exchange Server.
- State
- PUBLISHED
- Published
- Nov 14, 2018
- Updated
- Oct 21, 2025
- Evidence coverage
- 97%
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: An elevation of privilege vulnerability exists in Microsoft Exchange Server, aka "Microsoft Exchange Server Elevation of Privilege Vulnerability." This affects Microsoft Exchange Server.
Inspect raw assertion
- Field
container- Value
- An elevation of privilege vulnerability exists in Microsoft Exchange Server, aka "Microsoft Exchange Server Elevation of Privilege Vulnerability." This affects Microsoft Exchange Server.
- 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: 27.36% probability · 97.91th percentile
Inspect raw assertion
- Field
model_probability- Value
- Probability 0.273550000000; percentile 0.979110000000
FIRST EPSS · score date Aug 27, 2026 · 97.9th percentile · first observed Aug 27, 2026
NVD · 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
An elevation of privilege vulnerability exists in Microsoft Exchange Server, aka "Microsoft Exchange Server Elevation of Privilege Vulnerability." This affects Microsoft Exchange Server.
Inspect raw assertion
- Field
container- Value
- An elevation of privilege vulnerability exists in Microsoft Exchange Server, aka "Microsoft Exchange Server Elevation of Privilege Vulnerability." This affects Microsoft Exchange Server.
Microsoft Exchange Server Privilege Escalation Vulnerability
Inspect raw assertion
- Field
observed_exploitation- Value
- Microsoft Exchange Server Privilege Escalation Vulnerability
27.36% probability · 97.91th percentile
Inspect raw assertion
- Field
model_probability- Value
- Probability 0.273550000000; percentile 0.979110000000
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
2 scope groups
Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "2010"}, {"status": "affected", "version": "2013"}, {"status": "affected", "version": "2016"}, {"status": "affected", "version": "2019"}]product-d87daca995d075bf30565cc429e7242a47683272975068df1d327ec1d8ff609cLinked exactInspect raw assertions
cpe:2.3:a:microsoft:exchange_server:2013:-:*:*:*:*:*:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 1
- Logic
- OR
- Version bounds
- No explicit bounds
- Match ID
27ef8db7-d5a0-47a8-9f69-7d0259490d69
cpe:2.3:a:microsoft:exchange_server:2016:-:*:*:*:*:*:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 2
- Logic
- OR
- Version bounds
- No explicit bounds
- Match ID
8039fba1-73d4-4ff2-b183-0dcc961cbff7
cpe:2.3:a:microsoft:exchange_server:2019:-:*:*:*:*:*:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 3
- Logic
- OR
- Version bounds
- No explicit bounds
- Match ID
40d8a6db-9225-4a3f-ad76-192f6cccf002
cpe:2.3:a:microsoft:exchange_server:2010:-:*:*:*:*:*:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 0
- Logic
- OR
- Version bounds
- No explicit bounds
- Match ID
1e3d7891-e16d-4106-8f81-df93590affd2
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
- 4
- Mapping revision
- cpe23-exact-mapping-v1
- Observed cutoff
- Aug 27, 2026
Retained assertion IDs
2001d0de-aa4d-4dbb-b1a5-d13d672ac51028d31c44-c76a-4c4c-8629-904c07f66d647fecd40e-17e2-4f00-abaf-6f80173ec342aae3acd8-c73f-49be-a82c-b247bfae5552Canonical 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
- 1
- Mapping revision
- cpe23-exact-mapping-v1
- Observed cutoff
- Aug 27, 2026
Retained assertion IDs
95174459-65cc-4dfa-a505-60632ded775dAssessments
CVSS by origin
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:NAV:N/AC:M/Au:N/C:P/I:P/A:NCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:NCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:NDirect CVE/CNA normalized decisions
CISA-ADP
CVSS 3.1 · Secondary · Independent enrichment · rank 2
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N- Validation
- Valid match
- Recomputed
- 7.4
- 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.