CVE-2026-109783: Vulnerability in Mozilla Firefox
Description
Mitigation bypass in the File Handling component. This vulnerability was fixed in Firefox ESR 153.5 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 released a fix for this vulnerability in Firefox ESR 153.5.
Potential Impact
The vulnerability could allow attackers to bypass security mitigations in the file handling process of Firefox, potentially increasing the risk of exploitation related to file operations. However, no known exploits in the wild have been reported.
Mitigation Recommendations
Mozilla has released an official fix in Firefox ESR 153.5. Users and administrators should update to version 153.5 or later to remediate this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-10-13T00:49:22.774Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-108/","vendor":"Mozilla"}]
Threat ID: 6ace2c542cdf04f65661d5b3
Added to database: 10/13/2026, 13:04:20 UTC
Last enriched: 10/13/2026, 13:18:43 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 9
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