CVE-2026-109749: Vulnerability in Mozilla Firefox
Description
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.
CVSS v3.1
Score 5.4medium
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a use-after-free condition within the JavaScript WebAssembly component of Mozilla Firefox. Such a flaw could potentially allow for memory corruption issues. Mozilla released a fix for this vulnerability in Firefox version 158.
Potential Impact
The vulnerability could lead to memory corruption due to use-after-free in the WebAssembly component, which may affect the stability or security of the browser. However, no active exploitation has been reported.
Mitigation Recommendations
Users should update to Firefox version 158 or later to remediate this vulnerability. The vendor advisory confirms that the issue is fixed in this version.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-10-13T00:29:54.031Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-106/","vendor":"Mozilla"}]
Threat ID: 6ace2c4b2cdf04f65661d54c
Added to database: 10/13/2026, 13:04:11 UTC
Last enriched: 10/13/2026, 13:48:20 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 3
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