CVE-2026-100818

Published Sep 29, 2026

Last updated 5 hours ago

Overview

Description
Sandbox escape due to use-after-free in the Widget: Gtk component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.
Source
security@mozilla.org
NVD status
Analyzed
Products
firefox, thunderbird

Risk scores

CVSS 3.1

Type
Secondary
Base score
9.6
Impact score
6
Exploitability score
2.8
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Severity
CRITICAL

Weaknesses

134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-416

Social media

Hype score
Not currently trending

Configurations