Firefox Sandbox Escape via Widget Boundaries fixed in v156/ESR 153.3
CVE-2026-92071 Published on September 15, 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 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3.
Vulnerability Analysis
CVE-2026-92071 can be exploited with network access, requires user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to be critical as this vulnerability has a high impact to the confidentiality, integrity and availability of this component.
Weakness Type
What is a Buffer Overflow Vulnerability?
The software performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer.
CVE-2026-92071 has been classified to as a Buffer Overflow vulnerability or weakness.
Products Associated with CVE-2026-92071
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Affected Versions
Mozilla Firefox:- Version 153.3, <= 153.* is unaffected.
- Version 156, <= * is unaffected.
- Version 153.3, <= 153.* is unaffected.
- Version 156, <= * is unaffected.