CVE-2026-84140EPSS p19.2%

CVE-2026-84140CVE-2026-84140

mozilla / firefox

Description

Site isolation issue in the DOM: Navigation component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.

Scoring

CVSS 9.8 ()
VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS0.29% probability of exploitation · percentile 19.2% · 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.