CVE-2026-2778
Sandbox escape due to incorrect boundary conditions in the DOM: Core & HTML component
CVSS Score
10.0
EPSS Score
0.1%
EPSS Percentile
23th
Sandbox escape due to incorrect boundary conditions in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.
| Vendor | mozilla |
| Product | firefox |
| Ecosystems | |
| Industries | Technology |
| Published | Feb 24, 2026 |
| Last Updated | Apr 16, 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=2016358 mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-13/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-14/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-15/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-16/ mozilla.org: https://www.mozilla.org/security/advisories/mfsa2026-17/
Credits
Sajeeb Lohani