CVE-2026-2776
Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software
CVSS Score
10.0
EPSS Score
0.1%
EPSS Percentile
23th
Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. 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=2015266 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