CVE-2026-100784 - Vulnerability Details - OpenCVE

Use-after-free in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

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=2070264
https://www.mozilla.org/security/advisories/mfsa2026-100/
https://www.mozilla.org/security/advisories/mfsa2026-97/
https://www.mozilla.org/security/advisories/mfsa2026-98/
https://www.mozilla.org/security/advisories/mfsa2026-99/

History

Tue, 29 Sep 2026 15:30:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-416
Metrics		cvssV3_1 `{'score': 8.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/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		Use-after-free in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
Title		Use-after-free in the Layout: Text and Fonts component
References		https://bugzilla.mozilla.org/show_bug.cgi?id=2070264 https://www.mozilla.org/security/advisories/mfsa2026-100/ https://www.mozilla.org/security/advisories/mfsa2026-97/ https://www.mozilla.org/security/advisories/mfsa2026-98/ https://www.mozilla.org/security/advisories/mfsa2026-99/

Projects

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MITRE

Status: PUBLISHED

Assigner: mozilla

Published: 2026-09-29T12:36:09.021Z

Updated: 2026-09-29T14:49:15.264Z

Reserved: 2026-09-26T19:17:03.000Z

Link: CVE-2026-100784

Vulnrichment

Updated: 2026-09-29T14:40:29.931Z

NVD

Status : Received

Published: 2026-09-29T13:17:43.357

Modified: 2026-09-29T15:17:14.030

Link: CVE-2026-100784

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-416

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