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Evidence dossier
CVE-2021-1789
CVE-2021-1789
64.6–84.6Priority evidence range
gen-56ccdaf9Normalized restatement
A type confusion issue was addressed with improved state handling. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, tvOS 14.4, watchOS 7.3, iOS 14.4 and iPadOS 14.4, Safari 14.0.3. Processing maliciously crafted web content may lead to arbitrary code execution.
- State
- PUBLISHED
- Published
- Apr 2, 2021
- Updated
- Oct 21, 2025
- Evidence coverage
- 72%
2026-07-18 · v2026.06.15 · percentile 96.3%
Distinct CVSS assessments remain side by side; none are averaged.
Source comparison
Who said what
appleoriginal assertion
container
A type confusion issue was addressed with improved state handling. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, tvOS 14.4, watchOS 7.3, iOS 14.4 and iPadOS 14.4, Safari 14.0.3. Processing maliciously crafted web content may lead to arbitrary code execution.
Jul 19, 2026Original evidence ↗
CISA KEVoriginal assertion
observed_exploitation
Apple Multiple Products Type Confusion Vulnerability
Jul 19, 2026Original evidence ↗
FIRST EPSSoriginal assertion
model_probability
Probability 0.145420000000; percentile 0.962530000000
Jul 19, 2026Original evidence ↗
Applicability
Cited product scope
AppleiOS and iPadOS
[{"status": "affected", "version": "unspecified", "lessThan": "14.4", "versionType": "custom"}]unknownApplemacOS
[{"status": "affected", "version": "unspecified", "lessThan": "11.2", "versionType": "custom"}]unknownApplemacOS
[{"status": "affected", "version": "unspecified", "lessThan": "7.3", "versionType": "custom"}]unknownApplemacOS
[{"status": "affected", "version": "unspecified", "lessThan": "14.4", "versionType": "custom"}]unknownApplemacOS
[{"status": "affected", "version": "unspecified", "lessThan": "14.0", "versionType": "custom"}]unknownUnknown vendorUnknown product
cpe:2.3:a:webkitgtk:webkitgtk:*:*:*:*:*:*:*:*; end excluding 2.30.6supportedUnknown vendorUnknown product
cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*; end excluding 14.4supportedUnknown vendorUnknown product
cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*; end excluding 14.4supportedUnknown vendorUnknown product
cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*; start including 11.0; end excluding 11.2supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*; start including 10.14; end excluding 10.14.6supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*; start including 10.15; end excluding 10.15.7supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.14.6:-:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-004:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-005:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-006:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2019-007:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-001:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-002:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-003:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-004:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-005:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-006:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.14.6:security_update_2020-007:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.14.6:supplemental_update:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.14.6:supplemental_update_2:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.15.7:-:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:mac_os_x:10.15.7:supplemental_update:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*; end excluding 14.4supportedUnknown vendorUnknown product
cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*; end excluding 7.3supportedUnknown vendorUnknown product
cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*supportedAssessments
CVSS by origin
nvd@nist.govCVSS 3.1 · role Primary
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hnvd@nist.govCVSS 2.0 · role Primary
AV:N/AC:M/Au:N/C:P/I:P/A:P134c704f-9b21-4f2e-91b3-4a467353bcc0CVSS 3.1 · role Secondary
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HCISA-ADPCVSS 3.1 · role unknown
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HLimitations 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 is unknown in Public Core because no accepted canonical mapping-obligation ledger is present.
- Core replay supports the active and immediately prior generation; retrospective valid-at replay is deferred.