CVE-2026-84142EPSS p44.7%

CVE-2026-84142CVE-2026-84142

mozilla / firefox

Description

Internally found bugs present in Thunderbird 154. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155 and Thunderbird 155.

Scoring

CVSS 9.8 ()
VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS0.56% probability of exploitation · percentile 44.7% · 2026-10-05T12:00:23Z
Last modified2026-09-03
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.