CVE-2026-109740: Vulnerability in Mozilla Firefox
Description
Sandbox escape due to incorrect boundary conditions in the Widget: Win32 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 a sandbox escape due to incorrect boundary conditions in the Widget: Win32 component of Mozilla Firefox. The issue was addressed and fixed in Firefox 158 and Firefox ESR 153.5, preventing exploitation of this sandbox escape vector.
Potential Impact
The vulnerability could allow an attacker to escape the sandbox restrictions in Firefox on Windows systems, potentially leading to execution of code outside the sandbox environment. This could increase the impact of other exploits or malicious content by bypassing security containment.
Mitigation Recommendations
Users and administrators should update Mozilla Firefox to version 158 or later, or Firefox ESR to version 153.5 or later, to apply the official fix for this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-10-13T00:29:46.134Z
- 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: 6ace2c482cdf04f65661d540
Added to database: 10/13/2026, 13:04:08 UTC
Last enriched: 10/13/2026, 13:48:56 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 3
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