CVE-2026-109763: Vulnerability in Mozilla Firefox
Description
Mitigation bypass in the File Handling 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 mitigation bypass within the File Handling component of Mozilla Firefox. The flaw could potentially allow an attacker to circumvent security mitigations related to file handling. Mozilla has fixed this vulnerability in Firefox 158 and Firefox ESR 153.5.
Potential Impact
The vulnerability could allow bypassing security mitigations in the File Handling component, potentially increasing the risk of exploitation related to file operations. However, no known exploits in the wild have been reported.
Mitigation Recommendations
Users and administrators should update to Firefox 158 or later, or Firefox ESR 153.5 or later, to ensure the vulnerability is fully mitigated. Since official fixes are available, applying these updates is the recommended remediation.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-10-13T00:48:32.559Z
- 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: 6ace2c4f2cdf04f65661d566
Added to database: 10/13/2026, 13:04:15 UTC
Last enriched: 10/13/2026, 13:34:16 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 8
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