9.6
Critical
CVE-2026-109708 Sandbox escape due to incorrect boundary conditions in the Networking component
Description
Sandbox escape due to incorrect boundary conditions in the Networking component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, Thunderbird 153.5, and Firefox ESR 115.44.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 158 | earliest → < 158 | 158 |
| Firefox 153.5 | earliest → < 153.5 | 153.5 |
| Firefox 115.44 | earliest → < 115.44 | 115.44 |
| Thunderbird 158 | earliest → < 158 | 158 |
| Thunderbird 153.5 | earliest → < 153.5 | 153.5 |