CVE-2026-100794
Sandbox escape due to incorrect boundary conditions in the Internationalization component
CVSS Score
9.6
EPSS Score
0.2%
EPSS Percentile
4th
Sandbox escape due to incorrect boundary conditions in the Internationalization component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, and Firefox ESR 140.17.
| Vendor | mozilla |
| Product | thunderbird |
| Ecosystems | |
| Industries | Technology |
| Published | Sep 29, 2026 |
| Last Updated | Oct 1, 2026 |
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Affected Versions
Mozilla / Thunderbird
All versions affected Mozilla / Firefox
All versions affected References
bugzilla.mozilla.org: https://bugzilla.mozilla.org/show_bug.cgi?id=2028871 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-100/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-101/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-102/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-103/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-97/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-99/
Credits
Mozilla