CVE-2026-92021
Received Received - Intake

Use-after-free in Firefox ESR JavaScript Engine

Publication date: 2026-09-15

Last updated on: 2026-09-15

Assigner: Mozilla Corporation

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

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Meta Information

Published
2026-09-15
Last Modified
2026-09-15
Generated
2026-09-15
AI Q&A
2026-09-15
EPSS Evaluated
N/A
NVD
CVE-2026-92021
EUVD
EUVD-2026-78484

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
mozilla firefox_esr 140.16

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Exploitability

CWE
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KEV
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CWE ID Description
CWE-UNKNOWN

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Executive Summary

This is a use-after-free vulnerability in the JavaScript Engine's JIT component of Firefox ESR. Use-after-free occurs when a program continues to use memory after it has been freed, potentially leading to crashes or arbitrary code execution.

Detection Guidance

Detection of this vulnerability requires checking the installed version of Firefox ESR. If your system is running Firefox ESR 140.16 or later, it is not vulnerable. Otherwise, update immediately. No specific network or system commands are provided in the context to detect this issue.

Impact Analysis

An attacker could exploit this to crash the browser or run malicious code on your system. This may allow unauthorized access to sensitive data or control of your device if combined with other exploits.

Compliance Impact

The provided CVE data does not specify how this vulnerability impacts compliance with standards like GDPR or HIPAA. The description only mentions a use-after-free issue in Firefox ESR's JavaScript Engine JIT component, fixed in version 140.16.

Mitigation Strategies

Update Firefox ESR to version 140.16 or later to address the use-after-free vulnerability in the JavaScript Engine JIT component.

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