CVE-2026-92021

Use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox ESR 140.16 and Thunderbird 140.16.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2067208	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-92/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-95/	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mozilla:firefox::::::::
	cpe:2.3:a:mozilla:thunderbird::::::::

History

06 Oct 2026, 14:39

Type	Values Removed	Values Added
CPE		cpe:2.3:a:mozilla:firefox:::::::: cpe:2.3:a:mozilla:thunderbird::::::::
First Time		Mozilla thunderbird Mozilla Mozilla firefox
References	~~() https://bugzilla.mozilla.org/show_bug.cgi?id=2067208 -~~	() https://bugzilla.mozilla.org/show_bug.cgi?id=2067208 - Permissions Required
References	~~() https://www.mozilla.org/security/advisories/mfsa2026-92/ -~~	() https://www.mozilla.org/security/advisories/mfsa2026-92/ - Vendor Advisory
References	~~() https://www.mozilla.org/security/advisories/mfsa2026-95/ -~~	() https://www.mozilla.org/security/advisories/mfsa2026-95/ - Vendor Advisory

20 Sep 2026, 01:16

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 8.8
CWE		CWE-416

Information

Published : 2026-09-15 13:16

Updated : 2026-10-06 14:39

NVD link : CVE-2026-92021

Mitre link : CVE-2026-92021

CVE.ORG link : CVE-2026-92021

JSON object : View

Products Affected

mozilla

firefox
thunderbird

CWE

CWE-416

Use After Free

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