CVE-2019-17026
Mozilla: IonMonkey type confusion with StoreElementHole and FallibleStoreElement
Severity
CriticalRed Hat Product Security
CVSS 3.0
Review impact separately from score.
Published · January 8, 2020
Updated · November 21, 2025
Description
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.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.0 · 8.8CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE-843 · Access of Resource Using Incompatible Type ('Type Confusion')