9.6
Critical
CVE-2026-109740 Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component
Description
Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 158 | earliest → < 158 | 158 |
| Firefox 153.5 | earliest → < 153.5 | 153.5 |
| Thunderbird 158 | earliest → < 158 | 158 |
| Thunderbird 153.5 | earliest → < 153.5 | 153.5 |
References
- bugzilla.mozilla.org bugzilla.mozilla.org
- www.mozilla.org www.mozilla.org
- www.mozilla.org www.mozilla.org
- www.mozilla.org www.mozilla.org
- www.mozilla.org www.mozilla.org
Timeline
- Published
- Last modified
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