CVE-2026-109749 - Vulnerability Details - OpenCVE

Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact Low

Integrity Impact Low

Availability Impact None

User Interaction Required

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable no

Technical Impact partial

Vendors	Products
Mozilla	Firefox

No data.

No data.

References

Link	Providers
https://bugzilla.mozilla.org/show_bug.cgi?id=2067174
https://www.mozilla.org/security/advisories/mfsa2026-106/
https://www.mozilla.org/security/advisories/mfsa2026-109/

History

Tue, 13 Oct 2026 19:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Tue, 13 Oct 2026 18:30:00 +0000

Type	Values Removed	Values Added
Description	Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 158.	Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.
References		https://www.mozilla.org/security/advisories/mfsa2026-109/

Tue, 13 Oct 2026 16:30:00 +0000

Type	Values Removed	Values Added
First Time appeared		Mozilla Mozilla firefox
Vendors & Products		Mozilla Mozilla firefox

Tue, 13 Oct 2026 15:30:00 +0000

Type	Values Removed	Values Added
Weaknesses		CWE-416
Metrics		cvssV3_1 `{'score': 5.4, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N'}`

Tue, 13 Oct 2026 13:00:00 +0000

Type	Values Removed	Values Added
Description		Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 158.
Title		Use-after-free in the JavaScript: WebAssembly component
References		https://bugzilla.mozilla.org/show_bug.cgi?id=2067174 https://www.mozilla.org/security/advisories/mfsa2026-106/

MITRE

Status: PUBLISHED

Assigner: mozilla

Published: 2026-10-13T12:29:28.505Z

Updated: 2026-10-13T18:08:20.192Z

Reserved: 2026-10-13T00:29:54.031Z

Link: CVE-2026-109749

Vulnrichment

Updated: 2026-10-13T14:13:36.531Z

NVD

Status : Deferred

Published: 2026-10-13T13:17:25.783

Modified: 2026-10-13T19:18:39.043

Link: CVE-2026-109749

Redhat

No data.

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