CVE-2026-109745: Vulnerability in Mozilla Firefox
Description
Sandbox escape due to uninitialized memory in the DOM: Web Serial component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves uninitialized memory usage in the DOM Web Serial component of Mozilla Firefox, which can lead to sandbox escape. The flaw was addressed and fixed in Firefox 158 and Firefox ESR 153.5, preventing exploitation through this vector.
Potential Impact
Successful exploitation could allow an attacker to escape the browser's sandbox environment, potentially leading to execution of code outside the intended security boundaries. However, there are no known exploits in the wild at this time.
Mitigation Recommendations
Users should update to Firefox 158 or later, or Firefox ESR 153.5 or later, where this vulnerability has been fixed. Applying these official patches fully mitigates the risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-10-13T00:29:50.232Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-106/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-108/","vendor":"Mozilla"}]
Threat ID: 6ace2c4b2cdf04f65661d548
Added to database: 10/13/2026, 13:04:11 UTC
Last enriched: 10/13/2026, 13:48:33 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 3
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