CVE-2026-109733
Deferred Deferred - Pending Action

JIT Miscompilation in Firefox JavaScript Engine

Publication date: 2026-10-13

Last updated on: 2026-10-13

Assigner: Mozilla Corporation

Description
JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 158, Firefox ESR 115.43, and Firefox ESR 153.5.

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Meta Information

Published
2026-10-13
Last Modified
2026-10-13
Generated
2026-10-13
AI Q&A
2026-10-13
EPSS Evaluated
N/A
NVD
CVE-2026-109733
EUVD
EUVD-2026-98650

Affected Vendors & Products

Showing 2 associated CPEs
Vendor Product Version / Range
mozilla firefox 158
mozilla firefox esr

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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 JIT miscompilation vulnerability in the JavaScript Engine. It occurs when the Just-In-Time compiler incorrectly translates JavaScript code, leading to potential memory corruption or arbitrary code execution. It was fixed in Firefox 158 and specific Firefox ESR versions.

Impact Analysis

An attacker could exploit this to execute arbitrary code on your system, potentially leading to data theft, system compromise, or installation of malware. Users of affected Firefox versions are at risk until they update.

Mitigation Strategies

Update Firefox to version 158 or later, Firefox ESR 115.43 or later, or Firefox ESR 153.5 or later to address the JIT miscompilation vulnerability.

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