9.6
Critical
CVE-2026-8959 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 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Firefox 151 | earliest → < 151 | 151 |
| Firefox 140.11 | earliest → < 140.11 | 140.11 |
| Thunderbird 151 | earliest → < 151 | 151 |
| Thunderbird 140.11 | earliest → < 140.11 | 140.11 |
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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