CVE-2026-92064
Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component
CVSS Score
8.8
EPSS Score
0.1%
EPSS Percentile
4th
Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component. This vulnerability was fixed in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3.
| Vendor | mozilla |
| Product | firefox |
| Ecosystems | |
| Industries | Technology |
| Published | Sep 15, 2026 |
| Last Updated | Sep 21, 2026 |
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Affected Versions
Mozilla / Firefox
All versions affected Mozilla / Thunderbird
All versions affected References
bugzilla.mozilla.org: https://bugzilla.mozilla.org/show_bug.cgi?id=2057990 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-90/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-93/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-94/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-96/
Credits
Mozilla