Firefox 151 Win32 Widget Sandbox Escape - Boundary Condition Flaw
CVE-2026-8959 Published on May 19, 2026
Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component
Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component. This vulnerability was fixed in Firefox 151 and Firefox ESR 140.11.
Products Associated with CVE-2026-8959
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Affected Versions
Mozilla Firefox:- Version 140.11, <= 140.* is unaffected.
- Version 151, <= * is unaffected.