CVE-2026-109705
Sandbox escape, site isolation issue due to incorrect boundary conditions, use-after-free in the Networking component
- State
- Published
- Severity
- 9.6 Critical
- Published
- Oct 13, 2026
- Updated
- Oct 27, 2026
- Reserved
- Oct 13, 2026
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, Thunderbird 153.5, and Firefox ESR 115.44.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 9.6 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H | CISA-ADP |
Weaknesses
- CWE-416 Use After Free
Affected Products
| Product | Versions |
|---|---|
FirefoxMozilla |
|
ThunderbirdMozilla |
|
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=2040905
- https://www.mozilla.org/security/advisories/mfsa2026-106/
- https://www.mozilla.org/security/advisories/mfsa2026-108/
- https://www.mozilla.org/security/advisories/mfsa2026-109/
- https://www.mozilla.org/security/advisories/mfsa2026-110/
- https://www.mozilla.org/security/advisories/mfsa2026-119/
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