CyberICT

CVE-2026-84140

Mozilla · Published September 1, 2026

CVSS v3.1

CRITICAL
Patch availableGet patch

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.

Affected Products

  • Firefox < 153.2.0
  • Firefox < 155.0.0
  • Thunderbird < 153.2.0
  • Thunderbird < 155.0

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H