CVE-2026-109721: Vulnerability in Mozilla Firefox
Description
Incorrect boundary conditions in the JavaScript Engine: JIT 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
The vulnerability involves incorrect boundary conditions in the Just-In-Time (JIT) compilation component of the JavaScript Engine in Mozilla Firefox. This defect could potentially lead to unexpected behavior or security issues within the engine. Mozilla fixed this vulnerability in Firefox 158 and Firefox ESR 153.5.
Potential Impact
The vulnerability could allow for issues related to the JavaScript engine's execution due to boundary condition errors. The exact impact is not detailed in the provided data, and no known exploits in the wild have been reported.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 158 and Firefox ESR 153.5. Users and administrators should update to these versions or later to mitigate the risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-10-13T00:29:28.830Z
- 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: 6ace2c432cdf04f65661d4d7
Added to database: 10/13/2026, 13:04:03 UTC
Last enriched: 10/13/2026, 14:18:39 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 3
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