CVE-2026-109749
Received Received - Intake

Use-after-free in Firefox JavaScript WebAssembly

Publication date: 2026-10-13

Last updated on: 2026-10-13

Assigner: Mozilla Corporation

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

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Meta Information

Published
2026-10-13
Last Modified
2026-10-13
Generated
2026-10-19
AI Q&A
2026-10-13
EPSS Evaluated
2026-10-18
NVD
CVE-2026-109749
EUVD
EUVD-2026-98511

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
mozilla firefox 158

Helpful Resources

Exploitability

CWE
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KEV
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CWE ID Description
CWE-416 The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.

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Executive Summary

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

Impact Analysis

An attacker could exploit this to crash your browser or run malicious code on your system. This may allow them to steal data, install malware, or take control of your device.

Compliance Impact

The provided CVE data does not specify direct impacts on compliance with GDPR, HIPAA, or other standards. The vulnerability involves a use-after-free in Firefox's JavaScript WebAssembly component, which could potentially lead to memory corruption and arbitrary code execution. This may indirectly affect compliance by compromising data integrity or confidentiality if exploited, but no explicit details are provided.

Mitigation Strategies

Update Firefox to version 158 or later to address the use-after-free vulnerability in the JavaScript: WebAssembly component.

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