CVE-2026-100819 - Vulnerability Details - OpenCVE

Sandbox escape due to incorrect boundary conditions in the XPCOM 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 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=2071069
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 14:30:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-119
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 incorrect boundary conditions in the XPCOM component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
Title		Sandbox escape due to incorrect boundary conditions in the XPCOM component
References		https://bugzilla.mozilla.org/show_bug.cgi?id=2071069 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: 2026-09-29T12:36:29.199Z

Updated: 2026-09-29T14:06:36.354Z

Reserved: 2026-09-26T19:18:30.736Z

Link: CVE-2026-100819

Vulnrichment

Updated: 2026-09-29T14:06:29.087Z

NVD

Status : Received

Published: 2026-09-29T13:17:47.193

Modified: 2026-09-29T13:17:47.193

Link: CVE-2026-100819

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-119

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