Vulnerability · NVD

CVE-2026-100787

CVE-2026-100787, critical severity (CVSS 9.6): 2 tracked apps concerned, all fixed or indeterminable on their current version.

Published on 2026-09-29

Sandbox escape in the XUL component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.

Attack vector : Network No privileges required

Show raw CVSS vector

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

EPSS 0.32% exploit very unlikely percentile 22.8%

Tracked apps referencing this CVE

For each app: the affected range, the fixing version, and where the tracked app stands today.

Vulnerable CPE configurations (4)

Vendor	Product	Platform	Versions	CPE 2.3 URI
mozilla	firefox All platforms (wildcard)	All platforms (wildcard)	<153.4.0	cpe:2.3:a:mozilla:firefox::::::::
mozilla	firefox All platforms (wildcard)	All platforms (wildcard)	≥154.0.0 <157.0.0	cpe:2.3:a:mozilla:firefox::::::::
mozilla	thunderbird All platforms (wildcard)	All platforms (wildcard)	<153.4.0	cpe:2.3:a:mozilla:thunderbird::::::::
mozilla	thunderbird All platforms (wildcard)	All platforms (wildcard)	≥154.0 <157.0	cpe:2.3:a:mozilla:thunderbird::::::::

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