CISA KEV · catalog date Aug 18, 2026 · first observed Sep 1, 2026
Evidence dossier
CVE-2026-65400
An authentication issue was addressed with improved state management.
Exploited in the wild (CISA KEV since Aug 18, 2026). CVE Program source reports CVSS 3.1 9.8. EPSS estimates 1.7% exploit likelihood as of Oct 22, 2026.
As of Oct 22, 2026
Normalized restatement
An authentication issue was addressed with improved state management. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.7.9, macOS Sonoma 14.8.9, macOS Tahoe 26.6.1, macOS Tahoe 26.7. An attacker on the network may be able to authenticate to Screen Sharing without valid credentials.
- State
- PUBLISHED
- Published
- Aug 6, 2026
- Updated
- Sep 14, 2026
- Evidence coverage
- 85%
Evidence chronology
What was known when
- Source dateFirst observed by CASCACISA KEVOriginal evidence ↗
Exploitation cataloged: Apple macOS Improper Authentication Vulnerability
Inspect raw assertion
- Field
observed_exploitation- Value
- Apple macOS Improper Authentication Vulnerability
- Source dateSource date omittedFirst observed by CASCAappleOriginal evidence ↗
Record text: An authentication issue was addressed with improved state management. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.7.9, macOS Sonoma 14.8.9, macOS Tahoe 26.6.1, macOS Tahoe 26.7. An attacker on the network may be able to authenticate to Screen Sharing without valid credentials.
Inspect raw assertion
- Field
container- Value
- An authentication issue was addressed with improved state management. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.7.9, macOS Sonoma 14.8.9, macOS Tahoe 26.6.1, macOS Tahoe 26.7. An attacker on the network may be able to authenticate to Screen Sharing without valid credentials.
- 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 dateFirst observed by CASCAFIRST EPSSOriginal evidence ↗
EPSS score: 1.72% probability · 77.33th percentile
Inspect raw assertion
- Field
model_probability- Value
- Probability 0.017230000000; percentile 0.773280000000
FIRST EPSS · score date Oct 22, 2026 · 77.3th percentile · first observed Oct 22, 2026
CVE Program source · CVSS 3.1 · first observed Sep 15, 2026 · same-version scores align in this snapshot
Evidence detail
Source limits and decisions
Why each evidence state has this value
casca-unknown-reasons-v1The last verified source boundary remains in force for this claim.
- Revision
- evidence-policy-v1.1.0
- Cutoff
- Oct 22, 2026
- Resolution
- Review source contract
Eligible evidence is present for this bounded claim.
- Revision
- evidence-policy-v1.1.0
- Cutoff
- Oct 22, 2026
- Resolution
- None
Eligible evidence is present for this bounded claim.
- Revision
- casca-direct-cvss-eligibility-v1
- Cutoff
- Oct 22, 2026
- Resolution
- None
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
Apple macOS Improper Authentication Vulnerability
Inspect raw assertion
- Field
observed_exploitation- Value
- Apple macOS Improper Authentication Vulnerability
An authentication issue was addressed with improved state management. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.7.9, macOS Sonoma 14.8.9, macOS Tahoe 26.6.1, macOS Tahoe 26.7. An attacker on the network may be able to authenticate to Screen Sharing without valid credentials.
Inspect raw assertion
- Field
container- Value
- An authentication issue was addressed with improved state management. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.7.9, macOS Sonoma 14.8.9, macOS Tahoe 26.6.1, macOS Tahoe 26.7. An attacker on the network may be able to authenticate to Screen Sharing without valid credentials.
CISA ADP Vulnrichment
Inspect raw assertion
- Field
container- Value
- CISA ADP Vulnrichment
CVE Program Container
Inspect raw assertion
- Field
container- Value
- CVE Program Container
1.72% probability · 77.33th percentile
Inspect raw assertion
- Field
model_probability- Value
- Probability 0.017230000000; percentile 0.773280000000
Applicability
Cited product scope
4 scope groups
Canonical linkage remains open; the cited source assertion is retained below.
Inspect raw assertion
[{"status": "affected", "version": "0", "lessThan": "14.8.9", "versionType": "custom"}, {"status": "affected", "version": "0", "lessThan": "15.7.9", "versionType": "custom"}, {"status": "affected", "version": "0", "lessThan": "26.6.1", "versionType": "custom"}, {"status": "affected", "version": "0", "lessThan": "26.7", "versionType": "custom"}, {"status": "affected", "version": "0", "lessThan": "27", "versionType": "custom"}]Inspect raw assertion
cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*; start including 14.0; end excluding 14.8.9Inspect raw assertion
cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*; start including 15.0; end excluding 15.7.9Inspect raw assertion
cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*; start including 26.0; end excluding 26.6.1Affected-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
- 1
- Mapping revision
- cpe23-exact-mapping-v1
- Observed cutoff
- Oct 22, 2026
Retained assertion IDs
5b53579e-73d9-408a-b685-239379b89e3dCanonical 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
- 3
- Mapping revision
- cpe23-exact-mapping-v1
- Observed cutoff
- Oct 22, 2026
Retained assertion IDs
2e39e2c5-1cf2-4371-8ef7-f6ac09401f0e30a955ea-a591-41a0-af38-12fc9d8c322e7f0790ce-8331-46b9-9854-a7f6bbabab12Assessments
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:HDirect CVE/CNA normalized decisions
CISA-ADP
CVSS 3.1 · Secondary · Independent enrichment · rank 2
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- 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.