CVE-2019-9795

9.8 criticalEPSS 1.7%

A vulnerability where type-confusion in the IonMonkey just-in-time (JIT) compiler could potentially be used by malicious JavaScript to trigger a potentially exploitable crash. This vulnerability affects Thunderbird < 60.6, Firefox ESR < 60.6, and Firefox < 66.

Severity

CVSS 3.0

9.8 critical

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS: 1.7% chance of exploitation in the next 30 days; higher than 77% of CVEs (scores of 2026-10-31)
CWEs: CWE-617, CWE-843
Published: 2019-04-26
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

mozilla:firefox
mozilla:firefox_esr
mozilla:thunderbird

References

https://access.redhat.com/errata/RHSA-2019:0966
https://access.redhat.com/errata/RHSA-2019:1144
https://bugzilla.mozilla.org/show_bug.cgi?id=1514682
https://www.mozilla.org/security/advisories/mfsa2019-07/
https://www.mozilla.org/security/advisories/mfsa2019-08/

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