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Evidence dossier
CVE-2019-17026
CVE-2019-17026
gen-56ccdaf9Normalized restatement
Incorrect alias information in IonMonkey JIT compiler for setting array elements could lead to a type confusion. We are aware of targeted attacks in the wild abusing this flaw. This vulnerability affects Firefox ESR < 68.4.1, Thunderbird < 68.4.1, and Firefox < 72.0.1.
- State
- PUBLISHED
- Published
- Mar 2, 2020
- Updated
- Oct 21, 2025
- Evidence coverage
- 72%
2026-07-18 · v2026.06.15 · percentile 98.6%
Distinct CVSS assessments remain side by side; none are averaged.
Source comparison
Who said what
Incorrect alias information in IonMonkey JIT compiler for setting array elements could lead to a type confusion. We are aware of targeted attacks in the wild abusing this flaw. This vulnerability affects Firefox ESR < 68.4.1, Thunderbird < 68.4.1, and Firefox < 72.0.1.
Mozilla Firefox And Thunderbird Type Confusion Vulnerability
Probability 0.434220000000; percentile 0.985940000000
Applicability
Cited product scope
[{"status": "affected", "version": "unspecified", "lessThan": "72.0.1", "versionType": "custom"}]unknown[{"status": "affected", "version": "unspecified", "lessThan": "68.4.1", "versionType": "custom"}]unknown[{"status": "affected", "version": "unspecified", "lessThan": "68.4.1", "versionType": "custom"}]unknowncpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*; end excluding 72.0.1supportedcpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*; end excluding 68.4.1supportedcpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*; end excluding 68.4.1supportedcpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*supportedAssessments
CVSS by origin
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HAV:N/AC:M/Au:N/C:P/I:P/A:PCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HCVSS: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.