CVE-2026-109705: Vulnerability in Mozilla Firefox
Description
Sandbox escape, site isolation issue due to incorrect boundary conditions, use-after-free in the Networking component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
CVSS v3.1
Score 9.6critical
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in Mozilla Firefox allows sandbox escape and compromises site isolation due to incorrect boundary conditions leading to a use-after-free condition in the Networking component. The flaw was resolved by Mozilla in Firefox 158 and Firefox ESR 153.5, mitigating the risk of exploitation.
Potential Impact
The vulnerability could allow an attacker to escape the browser sandbox and bypass site isolation protections, potentially leading to unauthorized access or code execution outside the intended security boundaries. However, there are no known exploits in the wild at this time.
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 remediate the issue.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-10-13T00:29:14.767Z
- 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: 6ace2c402cdf04f65661caf2
Added to database: 10/13/2026, 13:04:00 UTC
Last enriched: 10/13/2026, 14:19:47 UTC
Last updated: 10/13/2026, 18:57:33 UTC
Views: 9
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