# CASCA evidence receipt — CVE-2018-20753

- Generation: `gen-409cbd0c74ff4feb70e4944e6b98ce40`
- As known: 2026-07-21T08:13:17.697275+00:00
- Comparison: gen-56ccdaf914f7b4be95b689ccae7dc20d
- Score policy: public-priority-v1.0.1
- Conflict: present

## Source assertions

- **CISA-ADP** (independent_enrichment): container — CISA ADP Vulnrichment
  - Observed: 2026-07-19T04:27:06.398189+00:00
  - Citation: https://www.cve.org/CVERecord?id=CVE-2018-20753
- **CVE** (derivative_copy): container — CVE Program Container
  - Observed: 2026-07-19T04:27:06.398189+00:00
  - Citation: https://www.cve.org/CVERecord?id=CVE-2018-20753
- **mitre** (original_assertion): container — Kaseya VSA RMM before R9.3 9.3.0.35, R9.4 before 9.4.0.36, and R9.5 before 9.5.0.5 allows unprivileged remote attackers to execute PowerShell payloads on all managed devices. In January 2018, attackers actively exploited this vulnerability in the wild.
  - Observed: 2026-07-19T04:27:06.398189+00:00
  - Citation: https://www.cve.org/CVERecord?id=CVE-2018-20753
- **CISA KEV** (original_assertion): observed_exploitation — Kaseya VSA Remote Code Execution Vulnerability
  - Observed: 2026-07-19T04:54:04.25158+00:00
  - Citation: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
- **FIRST EPSS** (original_assertion): model_probability — Probability 0.293360000000; percentile 0.979650000000
  - Observed: 2026-07-19T04:54:35.756809+00:00
  - Citation: https://www.first.org/epss/data_stats.html

## CVSS assessments

- **nvd@nist.gov** (Primary, CVSS 3.1): 9.8 — score eligible
  - Evidence class: nvd_enrichment_exact; source rank: 0
  - Validation: valid_match
  - Vector: `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
- **nvd@nist.gov** (Primary, CVSS 2.0): 7.5 — score eligible
  - Evidence class: nvd_enrichment_exact; source rank: 0
  - Validation: valid_match
  - Vector: `AV:N/AC:L/Au:N/C:P/I:P/A:P`
- **134c704f-9b21-4f2e-91b3-4a467353bcc0** (Secondary, CVSS 3.1): 9.8 — score eligible
  - Evidence class: registered_adp_or_other; source rank: 2
  - Validation: valid_match
  - Vector: `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
- **CISA-ADP** (unknown, CVSS 3.1): 9.8 — display only
  - Evidence class: direct_cve_record_display_only; source rank: not applicable
  - Validation: display-only direct record assessment
  - Vector: `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`

## Applicability scope

- **n/a · n/a** (direct_source; unknown)
  - Versions: [{"status": "affected", "version": "n/a"}]
- **kaseya · virtual_system_administrator** (vulnerable_target; supported)
  - Versions: Any version (unconstrained) (>= 9.3, < 9.3.0.35); Any version (unconstrained) (>= 9.4, < 9.4.0.36); Any version (unconstrained) (>= 9.5, < 9.5.0.5)
  - Canonical identity: `product-0debe2e9eda91eaeb06a1e3fa6a11b2d31264986c4f67500f6a6ed3a572c40c5`
  - Official link states: linked_exact
  - Criterion (linked_exact, vulnerable_target): `cpe:2.3:a:kaseya:virtual_system_administrator:*:*:*:*:*:*:*:*`
  - Criterion (linked_exact, vulnerable_target): `cpe:2.3:a:kaseya:virtual_system_administrator:*:*:*:*:*:*:*:*`
  - Criterion (linked_exact, vulnerable_target): `cpe:2.3:a:kaseya:virtual_system_administrator:*:*:*:*:*:*:*:*`

## Identity source boundaries

- **cpe_dictionary**: 1775266 records through 2026-07-21T06:45:29.809553+00:00
  - Run: `27d65b0f-b718-4b4f-bb79-c47c68d09dfa`
- **cpe_match**: 643502 records through 2026-07-21T08:13:17.697275+00:00
  - Run: `955dae73-7302-438b-aee1-058d7cc5d48e`

## Limitations and unknowns

- 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; unresolved scope remains unknown.
- NVD-carried upstream facts remain derivative and are not independent corroboration.
- 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.
- Factor D remains unknown because WC-03 has not converted canonical CPE mappings into generation-bound mapping obligations; canonical identity alone does not score applicability.
- Core replay supports the active and immediately prior generation; retrospective valid-at replay is deferred.

Generated from CASCA normalized evidence. This receipt is not proof that an asset is affected, unaffected, safe, or fixed.