CVE-2026-100819

CriticalCVSS 9.6/10Last modified Oct 5, 2026

Description

Sandbox escape due to incorrect boundary conditions in the XPCOM component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.

Metrics

CVSS 3.1 9.6/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

Weakness enumeration

CWE-119

Affected software

No affected versions have been published.

Timeline

Published
Sep 29, 2026
Last modified
Oct 5, 2026
NVD status
Analyzed

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CVE-2026-100819: Critical severity, CVSS 9.6 | Vulnix