CVE-2026-100818 - Vulnerability Details - OpenCVE

Sandbox escape due to use-after-free in the Widget: Gtk component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Changed

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction Required

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable no

Technical Impact total

No data.

No data.

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://bugzilla.mozilla.org/show_bug.cgi?id=2069399
https://www.mozilla.org/security/advisories/mfsa2026-100/
https://www.mozilla.org/security/advisories/mfsa2026-97/
https://www.mozilla.org/security/advisories/mfsa2026-99/

History

Tue, 29 Sep 2026 14:30:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-416
Metrics		cvssV3_1 `{'score': 9.6, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H'}` ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Tue, 29 Sep 2026 13:15:00 +0000

Type	Values Removed	Values Added
Description		Sandbox escape due to use-after-free in the Widget: Gtk component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17.
Title		Sandbox escape due to use-after-free in the Widget: Gtk component
References		https://bugzilla.mozilla.org/show_bug.cgi?id=2069399 https://www.mozilla.org/security/advisories/mfsa2026-100/ https://www.mozilla.org/security/advisories/mfsa2026-97/ https://www.mozilla.org/security/advisories/mfsa2026-99/

Projects

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MITRE

Status: PUBLISHED

Assigner: mozilla

Published: 2026-09-29T12:36:28.602Z

Updated: 2026-09-29T13:13:29.094Z

Reserved: 2026-09-26T19:18:28.415Z

Link: CVE-2026-100818

Vulnrichment

Updated: 2026-09-29T13:11:14.764Z

NVD

Status : Received

Published: 2026-09-29T13:17:47.037

Modified: 2026-09-29T14:17:17.550

Link: CVE-2026-100818

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-416

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