CVE-2026-92035
Sandbox escape due to incorrect boundary conditions in the Graphics component. This vulnerability was fixed in Thunderbird 140.17, Firefox 156, Firefox ESR 153.3, Thunderbird 156, Thunderbird 153.3, Firefox ESR 115.42, and Firefox ESR 140.17.
- Published Sep 15, 2026
- CVSS 9.6 critical
- 0.4% chance of exploitation in the next 30 days (EPSS)
- A fix is available