CISA KEV · catalog date Apr 11, 2022 · first observed Jul 19, 2026
Evidence dossier
CVE-2021-42278
Active Directory Domain Services Elevation of Privilege Vulnerability
Exploited in the wild (CISA KEV since Apr 11, 2022). microsoft reports CVSS 3.1 7.5. EPSS estimates 72.0% exploit likelihood as of Aug 26, 2026.
As of Aug 27, 2026
Normalized restatement
Active Directory Domain Services Elevation of Privilege Vulnerability
- State
- PUBLISHED
- Published
- Nov 10, 2021
- Updated
- Aug 6, 2026
- Evidence coverage
- 85%
Evidence chronology
What was known when
- Source dateFirst observed by CASCACISA KEVOriginal evidence ↗
Exploitation cataloged: Microsoft Active Directory Domain Services Privilege Escalation Vulnerability
Inspect raw assertion
- Field
observed_exploitation- Value
- Microsoft Active Directory Domain Services Privilege Escalation Vulnerability
- 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: Active Directory Domain Services Elevation of Privilege Vulnerability
Inspect raw assertion
- Field
container- Value
- Active Directory Domain Services Elevation of Privilege Vulnerability
- Source dateFirst observed by CASCAFIRST EPSSOriginal evidence ↗
EPSS score: 72.03% probability · 99.38th percentile
Inspect raw assertion
- Field
model_probability- Value
- Probability 0.720270000000; percentile 0.993810000000
FIRST EPSS · score date Aug 26, 2026 · 99.4th percentile · first observed Aug 26, 2026
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-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
Microsoft Active Directory Domain Services Privilege Escalation Vulnerability
Inspect raw assertion
- Field
observed_exploitation- Value
- Microsoft Active Directory Domain Services Privilege Escalation Vulnerability
CISA ADP Vulnrichment
Inspect raw assertion
- Field
container- Value
- CISA ADP Vulnrichment
CVE Program Container
Inspect raw assertion
- Field
container- Value
- CVE Program Container
Active Directory Domain Services Elevation of Privilege Vulnerability
Inspect raw assertion
- Field
container- Value
- Active Directory Domain Services Elevation of Privilege Vulnerability
72.03% probability · 99.38th percentile
Inspect raw assertion
- Field
model_probability- Value
- Probability 0.720270000000; percentile 0.993810000000
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
23 scope groups
Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "6.1.0", "lessThan": "6.1.7601.25769", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "6.0.0", "lessThan": "6.1.7601.25769", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "6.0.0", "lessThan": "6.0.6003.21282", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "6.0.0", "lessThan": "6.0.6003.21282", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "6.0.0", "lessThan": "6.0.6003.21282", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "6.2.0", "lessThan": "6.2.9200.23517", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "6.3.0", "lessThan": "6.3.9600.20174", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "6.3.0", "lessThan": "6.3.9600.20174", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "6.2.0", "lessThan": "6.2.9200.23517", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.14393.4770", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.14393.4770", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.17763.2300", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.17763.2300", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.20348.350", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.19041.1348", "versionType": "custom"}]Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "10.0.0", "lessThan": "10.0.19042.1348", "versionType": "custom"}]product-571f6df0fa50d71be9551414060ed8bfcdb500437871cf9595b7fa6b034cecbdLinked exactInspect raw assertion
cpe:2.3:o:microsoft:windows_server_2004:*:*:*:*:*:*:*:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 0
- Logic
- OR
- Version bounds
- through excluding 10.0.19041.1348
- Match ID
4cc5d95f-2823-475a-a466-1a4a5b328e88
product-217b1ab3d25f361a639824f86753d418b35aa2a816ee370bb71b5d1dd883d87aLinked exactInspect raw assertions
cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 2
- Logic
- OR
- Version bounds
- No explicit bounds
- Match ID
af07a81d-12e5-4b1d-bff9-c8d08c32ff4f
cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:*:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 1
- Logic
- OR
- Version bounds
- No explicit bounds
- Match ID
5f422a8c-2c4e-42c8-b420-e0728037e15c
product-5a80416e92fed0cddbb3d4f3840218b448dee11159824ad25a0353da566963feLinked exactInspect raw assertions
cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 3
- Logic
- OR
- Version bounds
- No explicit bounds
- Match ID
a7df96f8-ba6a-4780-9ca3-f719b3f81074
cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 4
- Logic
- OR
- Version bounds
- No explicit bounds
- Match ID
db18c4ce-5917-401e-acf7-2747084fd36e
product-02e254d111ce604757a15650ef469f4f8365d6247da82ce3ac2695c3cfc7dc5fLinked exactInspect raw assertion
cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 5
- Logic
- OR
- Version bounds
- through excluding 10.0.14393.4770
- Match ID
572bdefc-d3e8-4ff0-b91e-d21f42d2b82d
product-25a2932c0bbcb648f7e391c8b9d34c734e5085444c03c1c206b9d4c4baa80b25Linked exactInspect raw assertion
cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 6
- Logic
- OR
- Version bounds
- through excluding 10.0.17763.2300
- Match ID
74a5af5d-c59c-4093-a4c0-3be230e7637f
product-d196d31962e613955a91e33e795c22dcfa7bf25173abebaca616a6350cce9ce1Linked exactInspect raw assertion
cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 7
- Logic
- OR
- Version bounds
- through excluding 10.0.20348.350
- Match ID
b662e504-15e6-4d85-8463-bbe9435790cc
product-457c0c3b89fb1cf896e8491223eac8b0cb1ea61ce3174f915e4fe1032759d5a2Linked exactInspect raw assertion
cpe:2.3:o:microsoft:windows_server_20h2:*:*:*:*:*:*:*:*- Official link
- Linked exact
- Role
- Vulnerable target
- Configuration
- 0 · node/0 · match 8
- Logic
- OR
- Version bounds
- through excluding 10.0.19042.1348
- Match ID
81674128-32b2-4825-8e69-6047db81134c
Affected-product evidence
Accepted scope and product mapping
0 canonical links · 2 source-reported links
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
- 16
- Mapping revision
- cpe23-exact-mapping-v1
- Observed cutoff
- Aug 27, 2026
Retained assertion IDs
0934c56c-1279-43ae-bdb6-9db291e55a5c0b91fbbe-a035-4406-854b-67b87c2841940cb997c8-8b74-4e6a-99e6-1b1ca53a60a410f02be0-57e0-4f34-b7f5-63b21cadd865142e6ad1-64db-44a7-9e8d-48d202425f7a1672f79d-fbdd-42c3-a13f-9b649f3332ac1ab5080a-72df-42b8-9147-155a49ed14d428f43dc7-041d-4b9a-8cb2-ea23a0dc8e4739dc44ad-da04-4f68-a66c-ba6658651f2c451ee8f2-823b-4372-a511-015c9e081e985cca0bb3-cb26-4d0c-abf6-dfc4aa828145676cb9eb-ee77-45c9-85c8-e7426128eeb968423a66-883c-4214-95e4-0576a192563bae2e9946-f1a0-4588-8034-a413f71af87cbe2194d7-767c-40cc-b827-34a90f79da95fdfc48a6-4da2-44a2-bf50-a5b71a77b03bCanonical 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
- 9
- Mapping revision
- cpe23-exact-mapping-v1
- Observed cutoff
- Aug 27, 2026
Retained assertion IDs
09dc3033-ff3a-4a1b-96fb-34fce0a9be2e1ca0bea6-2700-4889-8b14-ec90796f8a443302d09b-83b2-48d4-833c-73e1adeefa0947545dee-72b3-4ca5-a4b7-d0c1ca5bfcc3671b3fc1-d1d6-4137-a14e-37fd2fcb8892680be36c-c155-4179-990c-a286928d36cf82d660db-99b1-4fb2-bac8-f3a2664871cdd2274fa2-ea5b-4518-b0c4-e48f1a9a7d90ffea729c-9d2e-4982-86ae-449f558ea979Assessments
CVSS by origin
AV:N/AC:L/Au:S/C:P/I:P/A:PCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:HCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:HCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:CDirect CVE/CNA normalized decisions
microsoft
CVSS 3.1 · Primary · Original assertion · rank 1
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C- Validation
- Valid match
- Recomputed
- 7.5
- 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.